1 // parse.cc -- Go frontend parser.
3 // Copyright 2009 The Go Authors. All rights reserved.
4 // Use of this source code is governed by a BSD-style
5 // license that can be found in the LICENSE file.
12 #include "statements.h"
13 #include "expressions.h"
16 // Struct Parse::Enclosing_var_comparison.
18 // Return true if v1 should be considered to be less than v2.
21 Parse::Enclosing_var_comparison::operator()(const Enclosing_var& v1,
22 const Enclosing_var& v2)
24 if (v1.var() == v2.var())
27 const std::string& n1(v1.var()->name());
28 const std::string& n2(v2.var()->name());
29 int i = n1.compare(n2);
35 // If we get here it means that a single nested function refers to
36 // two different variables defined in enclosing functions, and both
37 // variables have the same name. I think this is impossible.
43 Parse::Parse(Lex* lex, Gogo* gogo)
45 token_(Token::make_invalid_token(0)),
46 unget_token_(Token::make_invalid_token(0)),
47 unget_token_valid_(false),
56 // Return the current token.
61 if (this->unget_token_valid_)
62 return &this->unget_token_;
63 if (this->token_.is_invalid())
64 this->token_ = this->lex_->next_token();
68 // Advance to the next token and return it.
71 Parse::advance_token()
73 if (this->unget_token_valid_)
75 this->unget_token_valid_ = false;
76 if (!this->token_.is_invalid())
79 this->token_ = this->lex_->next_token();
83 // Push a token back on the input stream.
86 Parse::unget_token(const Token& token)
88 gcc_assert(!this->unget_token_valid_);
89 this->unget_token_ = token;
90 this->unget_token_valid_ = true;
93 // The location of the current token.
98 return this->peek_token()->location();
101 // IdentifierList = identifier { "," identifier } .
104 Parse::identifier_list(Typed_identifier_list* til)
106 const Token* token = this->peek_token();
109 if (!token->is_identifier())
111 error_at(this->location(), "expected identifier");
115 this->gogo_->pack_hidden_name(token->identifier(),
116 token->is_identifier_exported());
117 til->push_back(Typed_identifier(name, NULL, token->location()));
118 token = this->advance_token();
119 if (!token->is_op(OPERATOR_COMMA))
121 token = this->advance_token();
125 // ExpressionList = Expression { "," Expression } .
127 // If MAY_BE_SINK is true, the expressions in the list may be "_".
130 Parse::expression_list(Expression* first, bool may_be_sink)
132 Expression_list* ret = new Expression_list();
134 ret->push_back(first);
137 ret->push_back(this->expression(PRECEDENCE_NORMAL, may_be_sink, true,
140 const Token* token = this->peek_token();
141 if (!token->is_op(OPERATOR_COMMA))
144 // Most expression lists permit a trailing comma.
145 source_location location = token->location();
146 this->advance_token();
147 if (!this->expression_may_start_here())
149 this->unget_token(Token::make_operator_token(OPERATOR_COMMA,
156 // QualifiedIdent = [ PackageName "." ] identifier .
157 // PackageName = identifier .
159 // This sets *PNAME to the identifier and sets *PPACKAGE to the
160 // package or NULL if there isn't one. This returns true on success,
161 // false on failure in which case it will have emitted an error
165 Parse::qualified_ident(std::string* pname, Named_object** ppackage)
167 const Token* token = this->peek_token();
168 if (!token->is_identifier())
170 error_at(this->location(), "expected identifier");
174 std::string name = token->identifier();
175 bool is_exported = token->is_identifier_exported();
176 name = this->gogo_->pack_hidden_name(name, is_exported);
178 token = this->advance_token();
179 if (!token->is_op(OPERATOR_DOT))
186 Named_object* package = this->gogo_->lookup(name, NULL);
187 if (package == NULL || !package->is_package())
189 error_at(this->location(), "expected package");
190 // We expect . IDENTIFIER; skip both.
191 if (this->advance_token()->is_identifier())
192 this->advance_token();
196 package->package_value()->set_used();
198 token = this->advance_token();
199 if (!token->is_identifier())
201 error_at(this->location(), "expected identifier");
205 name = token->identifier();
209 error_at(this->location(), "invalid use of %<_%>");
213 if (package->name() == this->gogo_->package_name())
214 name = this->gogo_->pack_hidden_name(name,
215 token->is_identifier_exported());
220 this->advance_token();
225 // Type = TypeName | TypeLit | "(" Type ")" .
227 // ArrayType | StructType | PointerType | FunctionType | InterfaceType |
228 // SliceType | MapType | ChannelType .
233 const Token* token = this->peek_token();
234 if (token->is_identifier())
235 return this->type_name(true);
236 else if (token->is_op(OPERATOR_LSQUARE))
237 return this->array_type(false);
238 else if (token->is_keyword(KEYWORD_CHAN)
239 || token->is_op(OPERATOR_CHANOP))
240 return this->channel_type();
241 else if (token->is_keyword(KEYWORD_INTERFACE))
242 return this->interface_type();
243 else if (token->is_keyword(KEYWORD_FUNC))
245 source_location location = token->location();
246 this->advance_token();
247 Type* type = this->signature(NULL, location);
249 return Type::make_error_type();
252 else if (token->is_keyword(KEYWORD_MAP))
253 return this->map_type();
254 else if (token->is_keyword(KEYWORD_STRUCT))
255 return this->struct_type();
256 else if (token->is_op(OPERATOR_MULT))
257 return this->pointer_type();
258 else if (token->is_op(OPERATOR_LPAREN))
260 this->advance_token();
261 Type* ret = this->type();
262 if (this->peek_token()->is_op(OPERATOR_RPAREN))
263 this->advance_token();
266 if (!ret->is_error_type())
267 error_at(this->location(), "expected %<)%>");
273 error_at(token->location(), "expected type");
274 return Type::make_error_type();
279 Parse::type_may_start_here()
281 const Token* token = this->peek_token();
282 return (token->is_identifier()
283 || token->is_op(OPERATOR_LSQUARE)
284 || token->is_op(OPERATOR_CHANOP)
285 || token->is_keyword(KEYWORD_CHAN)
286 || token->is_keyword(KEYWORD_INTERFACE)
287 || token->is_keyword(KEYWORD_FUNC)
288 || token->is_keyword(KEYWORD_MAP)
289 || token->is_keyword(KEYWORD_STRUCT)
290 || token->is_op(OPERATOR_MULT)
291 || token->is_op(OPERATOR_LPAREN));
294 // TypeName = QualifiedIdent .
296 // If MAY_BE_NIL is true, then an identifier with the value of the
297 // predefined constant nil is accepted, returning the nil type.
300 Parse::type_name(bool issue_error)
302 source_location location = this->location();
305 Named_object* package;
306 if (!this->qualified_ident(&name, &package))
307 return Type::make_error_type();
309 Named_object* named_object;
311 named_object = this->gogo_->lookup(name, NULL);
314 named_object = package->package_value()->lookup(name);
315 if (named_object == NULL
317 && package->name() != this->gogo_->package_name())
319 // Check whether the name is there but hidden.
320 std::string s = ('.' + package->package_value()->unique_prefix()
321 + '.' + package->package_value()->name()
323 named_object = package->package_value()->lookup(s);
324 if (named_object != NULL)
326 const std::string& packname(package->package_value()->name());
327 error_at(location, "invalid reference to hidden type %<%s.%s%>",
328 Gogo::message_name(packname).c_str(),
329 Gogo::message_name(name).c_str());
336 if (named_object == NULL)
341 named_object = this->gogo_->add_unknown_name(name, location);
343 else if (named_object->is_type())
345 if (!named_object->type_value()->is_visible())
348 else if (named_object->is_unknown() || named_object->is_type_declaration())
356 error_at(location, "expected type");
357 return Type::make_error_type();
360 if (named_object->is_type())
361 return named_object->type_value();
362 else if (named_object->is_unknown() || named_object->is_type_declaration())
363 return Type::make_forward_declaration(named_object);
368 // ArrayType = "[" [ ArrayLength ] "]" ElementType .
369 // ArrayLength = Expression .
370 // ElementType = CompleteType .
373 Parse::array_type(bool may_use_ellipsis)
375 gcc_assert(this->peek_token()->is_op(OPERATOR_LSQUARE));
376 const Token* token = this->advance_token();
378 Expression* length = NULL;
379 if (token->is_op(OPERATOR_RSQUARE))
380 this->advance_token();
383 if (!token->is_op(OPERATOR_ELLIPSIS))
384 length = this->expression(PRECEDENCE_NORMAL, false, true, NULL);
385 else if (may_use_ellipsis)
387 // An ellipsis is used in composite literals to represent a
388 // fixed array of the size of the number of elements. We
389 // use a length of nil to represent this, and change the
390 // length when parsing the composite literal.
391 length = Expression::make_nil(this->location());
392 this->advance_token();
396 error_at(this->location(),
397 "use of %<[...]%> outside of array literal");
398 length = Expression::make_error(this->location());
399 this->advance_token();
401 if (!this->peek_token()->is_op(OPERATOR_RSQUARE))
403 error_at(this->location(), "expected %<]%>");
404 return Type::make_error_type();
406 this->advance_token();
409 Type* element_type = this->type();
411 return Type::make_array_type(element_type, length);
414 // MapType = "map" "[" KeyType "]" ValueType .
415 // KeyType = CompleteType .
416 // ValueType = CompleteType .
421 source_location location = this->location();
422 gcc_assert(this->peek_token()->is_keyword(KEYWORD_MAP));
423 if (!this->advance_token()->is_op(OPERATOR_LSQUARE))
425 error_at(this->location(), "expected %<[%>");
426 return Type::make_error_type();
428 this->advance_token();
430 Type* key_type = this->type();
432 if (!this->peek_token()->is_op(OPERATOR_RSQUARE))
434 error_at(this->location(), "expected %<]%>");
435 return Type::make_error_type();
437 this->advance_token();
439 Type* value_type = this->type();
441 if (key_type->is_error_type() || value_type->is_error_type())
442 return Type::make_error_type();
444 return Type::make_map_type(key_type, value_type, location);
447 // StructType = "struct" "{" { FieldDecl ";" } "}" .
452 gcc_assert(this->peek_token()->is_keyword(KEYWORD_STRUCT));
453 source_location location = this->location();
454 if (!this->advance_token()->is_op(OPERATOR_LCURLY))
456 source_location token_loc = this->location();
457 if (this->peek_token()->is_op(OPERATOR_SEMICOLON)
458 && this->advance_token()->is_op(OPERATOR_LCURLY))
459 error_at(token_loc, "unexpected semicolon or newline before %<{%>");
462 error_at(this->location(), "expected %<{%>");
463 return Type::make_error_type();
466 this->advance_token();
468 Struct_field_list* sfl = new Struct_field_list;
469 while (!this->peek_token()->is_op(OPERATOR_RCURLY))
471 this->field_decl(sfl);
472 if (this->peek_token()->is_op(OPERATOR_SEMICOLON))
473 this->advance_token();
474 else if (!this->peek_token()->is_op(OPERATOR_RCURLY))
476 error_at(this->location(), "expected %<;%> or %<}%> or newline");
477 if (!this->skip_past_error(OPERATOR_RCURLY))
478 return Type::make_error_type();
481 this->advance_token();
483 for (Struct_field_list::const_iterator pi = sfl->begin();
487 if (pi->type()->is_error_type())
489 for (Struct_field_list::const_iterator pj = pi + 1;
493 if (pi->field_name() == pj->field_name()
494 && !Gogo::is_sink_name(pi->field_name()))
495 error_at(pi->location(), "duplicate field name %<%s%>",
496 Gogo::message_name(pi->field_name()).c_str());
500 return Type::make_struct_type(sfl, location);
503 // FieldDecl = (IdentifierList CompleteType | TypeName) [ Tag ] .
504 // Tag = string_lit .
507 Parse::field_decl(Struct_field_list* sfl)
509 const Token* token = this->peek_token();
510 source_location location = token->location();
512 bool is_anonymous_pointer;
513 if (token->is_op(OPERATOR_MULT))
516 is_anonymous_pointer = true;
518 else if (token->is_identifier())
520 std::string id = token->identifier();
521 bool is_id_exported = token->is_identifier_exported();
522 source_location id_location = token->location();
523 token = this->advance_token();
524 is_anonymous = (token->is_op(OPERATOR_SEMICOLON)
525 || token->is_op(OPERATOR_RCURLY)
526 || token->is_op(OPERATOR_DOT)
527 || token->is_string());
528 is_anonymous_pointer = false;
529 this->unget_token(Token::make_identifier_token(id, is_id_exported,
534 error_at(this->location(), "expected field name");
535 while (!token->is_op(OPERATOR_SEMICOLON)
536 && !token->is_op(OPERATOR_RCURLY)
538 token = this->advance_token();
544 if (is_anonymous_pointer)
546 this->advance_token();
547 if (!this->peek_token()->is_identifier())
549 error_at(this->location(), "expected field name");
550 while (!token->is_op(OPERATOR_SEMICOLON)
551 && !token->is_op(OPERATOR_RCURLY)
553 token = this->advance_token();
557 Type* type = this->type_name(true);
560 if (this->peek_token()->is_string())
562 tag = this->peek_token()->string_value();
563 this->advance_token();
566 if (!type->is_error_type())
568 if (is_anonymous_pointer)
569 type = Type::make_pointer_type(type);
570 sfl->push_back(Struct_field(Typed_identifier("", type, location)));
572 sfl->back().set_tag(tag);
577 Typed_identifier_list til;
580 token = this->peek_token();
581 if (!token->is_identifier())
583 error_at(this->location(), "expected identifier");
587 this->gogo_->pack_hidden_name(token->identifier(),
588 token->is_identifier_exported());
589 til.push_back(Typed_identifier(name, NULL, token->location()));
590 if (!this->advance_token()->is_op(OPERATOR_COMMA))
592 this->advance_token();
595 Type* type = this->type();
598 if (this->peek_token()->is_string())
600 tag = this->peek_token()->string_value();
601 this->advance_token();
604 for (Typed_identifier_list::iterator p = til.begin();
609 sfl->push_back(Struct_field(*p));
611 sfl->back().set_tag(tag);
616 // PointerType = "*" Type .
619 Parse::pointer_type()
621 gcc_assert(this->peek_token()->is_op(OPERATOR_MULT));
622 this->advance_token();
623 Type* type = this->type();
624 if (type->is_error_type())
626 return Type::make_pointer_type(type);
629 // ChannelType = Channel | SendChannel | RecvChannel .
630 // Channel = "chan" ElementType .
631 // SendChannel = "chan" "<-" ElementType .
632 // RecvChannel = "<-" "chan" ElementType .
635 Parse::channel_type()
637 const Token* token = this->peek_token();
640 if (token->is_op(OPERATOR_CHANOP))
642 if (!this->advance_token()->is_keyword(KEYWORD_CHAN))
644 error_at(this->location(), "expected %<chan%>");
645 return Type::make_error_type();
648 this->advance_token();
652 gcc_assert(token->is_keyword(KEYWORD_CHAN));
653 if (this->advance_token()->is_op(OPERATOR_CHANOP))
656 this->advance_token();
659 Type* element_type = this->type();
660 return Type::make_channel_type(send, receive, element_type);
663 // Signature = Parameters [ Result ] .
665 // RECEIVER is the receiver if there is one, or NULL. LOCATION is the
666 // location of the start of the type.
668 // This returns NULL on a parse error.
671 Parse::signature(Typed_identifier* receiver, source_location location)
673 bool is_varargs = false;
674 Typed_identifier_list* params;
675 bool params_ok = this->parameters(¶ms, &is_varargs);
677 Typed_identifier_list* result = NULL;
678 if (this->peek_token()->is_op(OPERATOR_LPAREN)
679 || this->type_may_start_here())
681 if (!this->result(&result))
688 Function_type* ret = Type::make_function_type(receiver, params, result,
691 ret->set_is_varargs();
695 // Parameters = "(" [ ParameterList [ "," ] ] ")" .
697 // This returns false on a parse error.
700 Parse::parameters(Typed_identifier_list** pparams, bool* is_varargs)
704 if (!this->peek_token()->is_op(OPERATOR_LPAREN))
706 error_at(this->location(), "expected %<(%>");
710 Typed_identifier_list* params = NULL;
711 bool saw_error = false;
713 const Token* token = this->advance_token();
714 if (!token->is_op(OPERATOR_RPAREN))
716 params = this->parameter_list(is_varargs);
719 token = this->peek_token();
722 // The optional trailing comma is picked up in parameter_list.
724 if (!token->is_op(OPERATOR_RPAREN))
725 error_at(this->location(), "expected %<)%>");
727 this->advance_token();
736 // ParameterList = ParameterDecl { "," ParameterDecl } .
738 // This sets *IS_VARARGS if the list ends with an ellipsis.
739 // IS_VARARGS will be NULL if varargs are not permitted.
741 // We pick up an optional trailing comma.
743 // This returns NULL if some error is seen.
745 Typed_identifier_list*
746 Parse::parameter_list(bool* is_varargs)
748 source_location location = this->location();
749 Typed_identifier_list* ret = new Typed_identifier_list();
751 bool saw_error = false;
753 // If we see an identifier and then a comma, then we don't know
754 // whether we are looking at a list of identifiers followed by a
755 // type, or a list of types given by name. We have to do an
756 // arbitrary lookahead to figure it out.
758 bool parameters_have_names;
759 const Token* token = this->peek_token();
760 if (!token->is_identifier())
762 // This must be a type which starts with something like '*'.
763 parameters_have_names = false;
767 std::string name = token->identifier();
768 bool is_exported = token->is_identifier_exported();
769 source_location location = token->location();
770 token = this->advance_token();
771 if (!token->is_op(OPERATOR_COMMA))
773 if (token->is_op(OPERATOR_DOT))
775 // This is a qualified identifier, which must turn out
777 parameters_have_names = false;
779 else if (token->is_op(OPERATOR_RPAREN))
781 // A single identifier followed by a parenthesis must be
783 parameters_have_names = false;
787 // An identifier followed by something other than a
788 // comma or a dot or a right parenthesis must be a
789 // parameter name followed by a type.
790 parameters_have_names = true;
793 this->unget_token(Token::make_identifier_token(name, is_exported,
798 // An identifier followed by a comma may be the first in a
799 // list of parameter names followed by a type, or it may be
800 // the first in a list of types without parameter names. To
801 // find out we gather as many identifiers separated by
803 std::string id_name = this->gogo_->pack_hidden_name(name,
805 ret->push_back(Typed_identifier(id_name, NULL, location));
806 bool just_saw_comma = true;
807 while (this->advance_token()->is_identifier())
809 name = this->peek_token()->identifier();
810 is_exported = this->peek_token()->is_identifier_exported();
811 location = this->peek_token()->location();
812 id_name = this->gogo_->pack_hidden_name(name, is_exported);
813 ret->push_back(Typed_identifier(id_name, NULL, location));
814 if (!this->advance_token()->is_op(OPERATOR_COMMA))
816 just_saw_comma = false;
823 // We saw ID1 "," ID2 "," followed by something which
824 // was not an identifier. We must be seeing the start
825 // of a type, and ID1 and ID2 must be types, and the
826 // parameters don't have names.
827 parameters_have_names = false;
829 else if (this->peek_token()->is_op(OPERATOR_RPAREN))
831 // We saw ID1 "," ID2 ")". ID1 and ID2 must be types,
832 // and the parameters don't have names.
833 parameters_have_names = false;
835 else if (this->peek_token()->is_op(OPERATOR_DOT))
837 // We saw ID1 "," ID2 ".". ID2 must be a package name,
838 // ID1 must be a type, and the parameters don't have
840 parameters_have_names = false;
841 this->unget_token(Token::make_identifier_token(name, is_exported,
844 just_saw_comma = true;
848 // We saw ID1 "," ID2 followed by something other than
849 // ",", ".", or ")". We must be looking at the start of
850 // a type, and ID1 and ID2 must be parameter names.
851 parameters_have_names = true;
854 if (parameters_have_names)
856 gcc_assert(!just_saw_comma);
857 // We have just seen ID1, ID2 xxx.
859 if (!this->peek_token()->is_op(OPERATOR_ELLIPSIS))
863 error_at(this->location(), "%<...%> only permits one name");
865 this->advance_token();
868 for (size_t i = 0; i < ret->size(); ++i)
869 ret->set_type(i, type);
870 if (!this->peek_token()->is_op(OPERATOR_COMMA))
871 return saw_error ? NULL : ret;
872 if (this->advance_token()->is_op(OPERATOR_RPAREN))
873 return saw_error ? NULL : ret;
877 Typed_identifier_list* tret = new Typed_identifier_list();
878 for (Typed_identifier_list::const_iterator p = ret->begin();
882 Named_object* no = this->gogo_->lookup(p->name(), NULL);
885 no = this->gogo_->add_unknown_name(p->name(),
889 type = no->type_value();
890 else if (no->is_unknown() || no->is_type_declaration())
891 type = Type::make_forward_declaration(no);
894 error_at(p->location(), "expected %<%s%> to be a type",
895 Gogo::message_name(p->name()).c_str());
897 type = Type::make_error_type();
899 tret->push_back(Typed_identifier("", type, p->location()));
904 || this->peek_token()->is_op(OPERATOR_RPAREN))
905 return saw_error ? NULL : ret;
910 bool mix_error = false;
911 this->parameter_decl(parameters_have_names, ret, is_varargs, &mix_error);
912 while (this->peek_token()->is_op(OPERATOR_COMMA))
914 if (is_varargs != NULL && *is_varargs)
916 error_at(this->location(), "%<...%> must be last parameter");
919 if (this->advance_token()->is_op(OPERATOR_RPAREN))
921 this->parameter_decl(parameters_have_names, ret, is_varargs, &mix_error);
925 error_at(location, "invalid named/anonymous mix");
936 // ParameterDecl = [ IdentifierList ] [ "..." ] Type .
939 Parse::parameter_decl(bool parameters_have_names,
940 Typed_identifier_list* til,
944 if (!parameters_have_names)
947 source_location location = this->location();
948 if (!this->peek_token()->is_identifier())
950 if (!this->peek_token()->is_op(OPERATOR_ELLIPSIS))
954 if (is_varargs == NULL)
955 error_at(this->location(), "invalid use of %<...%>");
958 this->advance_token();
959 if (is_varargs == NULL
960 && this->peek_token()->is_op(OPERATOR_RPAREN))
961 type = Type::make_error_type();
964 Type* element_type = this->type();
965 type = Type::make_array_type(element_type, NULL);
971 type = this->type_name(false);
972 if (type->is_error_type()
973 || (!this->peek_token()->is_op(OPERATOR_COMMA)
974 && !this->peek_token()->is_op(OPERATOR_RPAREN)))
977 while (!this->peek_token()->is_op(OPERATOR_COMMA)
978 && !this->peek_token()->is_op(OPERATOR_RPAREN))
979 this->advance_token();
982 if (!type->is_error_type())
983 til->push_back(Typed_identifier("", type, location));
987 size_t orig_count = til->size();
988 if (this->peek_token()->is_identifier())
989 this->identifier_list(til);
992 size_t new_count = til->size();
995 if (!this->peek_token()->is_op(OPERATOR_ELLIPSIS))
999 if (is_varargs == NULL)
1000 error_at(this->location(), "invalid use of %<...%>");
1001 else if (new_count > orig_count + 1)
1002 error_at(this->location(), "%<...%> only permits one name");
1005 this->advance_token();
1006 Type* element_type = this->type();
1007 type = Type::make_array_type(element_type, NULL);
1009 for (size_t i = orig_count; i < new_count; ++i)
1010 til->set_type(i, type);
1014 // Result = Parameters | Type .
1016 // This returns false on a parse error.
1019 Parse::result(Typed_identifier_list** presults)
1021 if (this->peek_token()->is_op(OPERATOR_LPAREN))
1022 return this->parameters(presults, NULL);
1025 source_location location = this->location();
1026 Type* type = this->type();
1027 if (type->is_error_type())
1032 Typed_identifier_list* til = new Typed_identifier_list();
1033 til->push_back(Typed_identifier("", type, location));
1039 // Block = "{" [ StatementList ] "}" .
1041 // Returns the location of the closing brace.
1046 if (!this->peek_token()->is_op(OPERATOR_LCURLY))
1048 source_location loc = this->location();
1049 if (this->peek_token()->is_op(OPERATOR_SEMICOLON)
1050 && this->advance_token()->is_op(OPERATOR_LCURLY))
1051 error_at(loc, "unexpected semicolon or newline before %<{%>");
1054 error_at(this->location(), "expected %<{%>");
1055 return UNKNOWN_LOCATION;
1059 const Token* token = this->advance_token();
1061 if (!token->is_op(OPERATOR_RCURLY))
1063 this->statement_list();
1064 token = this->peek_token();
1065 if (!token->is_op(OPERATOR_RCURLY))
1067 if (!token->is_eof() || !saw_errors())
1068 error_at(this->location(), "expected %<}%>");
1070 // Skip ahead to the end of the block, in hopes of avoiding
1071 // lots of meaningless errors.
1072 source_location ret = token->location();
1074 while (!token->is_eof())
1076 if (token->is_op(OPERATOR_LCURLY))
1078 else if (token->is_op(OPERATOR_RCURLY))
1083 this->advance_token();
1087 token = this->advance_token();
1088 ret = token->location();
1094 source_location ret = token->location();
1095 this->advance_token();
1099 // InterfaceType = "interface" "{" [ MethodSpecList ] "}" .
1100 // MethodSpecList = MethodSpec { ";" MethodSpec } [ ";" ] .
1103 Parse::interface_type()
1105 gcc_assert(this->peek_token()->is_keyword(KEYWORD_INTERFACE));
1106 source_location location = this->location();
1108 if (!this->advance_token()->is_op(OPERATOR_LCURLY))
1110 source_location token_loc = this->location();
1111 if (this->peek_token()->is_op(OPERATOR_SEMICOLON)
1112 && this->advance_token()->is_op(OPERATOR_LCURLY))
1113 error_at(token_loc, "unexpected semicolon or newline before %<{%>");
1116 error_at(this->location(), "expected %<{%>");
1117 return Type::make_error_type();
1120 this->advance_token();
1122 Typed_identifier_list* methods = new Typed_identifier_list();
1123 if (!this->peek_token()->is_op(OPERATOR_RCURLY))
1125 this->method_spec(methods);
1126 while (this->peek_token()->is_op(OPERATOR_SEMICOLON))
1128 if (this->advance_token()->is_op(OPERATOR_RCURLY))
1130 this->method_spec(methods);
1132 if (!this->peek_token()->is_op(OPERATOR_RCURLY))
1134 error_at(this->location(), "expected %<}%>");
1135 while (!this->advance_token()->is_op(OPERATOR_RCURLY))
1137 if (this->peek_token()->is_eof())
1138 return Type::make_error_type();
1142 this->advance_token();
1144 if (methods->empty())
1150 Interface_type* ret = Type::make_interface_type(methods, location);
1151 this->gogo_->record_interface_type(ret);
1155 // MethodSpec = MethodName Signature | InterfaceTypeName .
1156 // MethodName = identifier .
1157 // InterfaceTypeName = TypeName .
1160 Parse::method_spec(Typed_identifier_list* methods)
1162 const Token* token = this->peek_token();
1163 if (!token->is_identifier())
1165 error_at(this->location(), "expected identifier");
1169 std::string name = token->identifier();
1170 bool is_exported = token->is_identifier_exported();
1171 source_location location = token->location();
1173 if (this->advance_token()->is_op(OPERATOR_LPAREN))
1175 // This is a MethodName.
1176 name = this->gogo_->pack_hidden_name(name, is_exported);
1177 Type* type = this->signature(NULL, location);
1180 methods->push_back(Typed_identifier(name, type, location));
1184 this->unget_token(Token::make_identifier_token(name, is_exported,
1186 Type* type = this->type_name(false);
1187 if (type->is_error_type()
1188 || (!this->peek_token()->is_op(OPERATOR_SEMICOLON)
1189 && !this->peek_token()->is_op(OPERATOR_RCURLY)))
1191 if (this->peek_token()->is_op(OPERATOR_COMMA))
1192 error_at(this->location(),
1193 "name list not allowed in interface type");
1195 error_at(location, "expected signature or type name");
1196 token = this->peek_token();
1197 while (!token->is_eof()
1198 && !token->is_op(OPERATOR_SEMICOLON)
1199 && !token->is_op(OPERATOR_RCURLY))
1200 token = this->advance_token();
1203 // This must be an interface type, but we can't check that now.
1204 // We check it and pull out the methods in
1205 // Interface_type::do_verify.
1206 methods->push_back(Typed_identifier("", type, location));
1210 // Declaration = ConstDecl | TypeDecl | VarDecl | FunctionDecl | MethodDecl .
1213 Parse::declaration()
1215 const Token* token = this->peek_token();
1216 if (token->is_keyword(KEYWORD_CONST))
1218 else if (token->is_keyword(KEYWORD_TYPE))
1220 else if (token->is_keyword(KEYWORD_VAR))
1222 else if (token->is_keyword(KEYWORD_FUNC))
1223 this->function_decl();
1226 error_at(this->location(), "expected declaration");
1227 this->advance_token();
1232 Parse::declaration_may_start_here()
1234 const Token* token = this->peek_token();
1235 return (token->is_keyword(KEYWORD_CONST)
1236 || token->is_keyword(KEYWORD_TYPE)
1237 || token->is_keyword(KEYWORD_VAR)
1238 || token->is_keyword(KEYWORD_FUNC));
1241 // Decl<P> = P | "(" [ List<P> ] ")" .
1244 Parse::decl(void (Parse::*pfn)(void*), void* varg)
1246 if (!this->peek_token()->is_op(OPERATOR_LPAREN))
1250 if (!this->advance_token()->is_op(OPERATOR_RPAREN))
1252 this->list(pfn, varg, true);
1253 if (!this->peek_token()->is_op(OPERATOR_RPAREN))
1255 error_at(this->location(), "missing %<)%>");
1256 while (!this->advance_token()->is_op(OPERATOR_RPAREN))
1258 if (this->peek_token()->is_eof())
1263 this->advance_token();
1267 // List<P> = P { ";" P } [ ";" ] .
1269 // In order to pick up the trailing semicolon we need to know what
1270 // might follow. This is either a '}' or a ')'.
1273 Parse::list(void (Parse::*pfn)(void*), void* varg, bool follow_is_paren)
1276 Operator follow = follow_is_paren ? OPERATOR_RPAREN : OPERATOR_RCURLY;
1277 while (this->peek_token()->is_op(OPERATOR_SEMICOLON)
1278 || this->peek_token()->is_op(OPERATOR_COMMA))
1280 if (this->peek_token()->is_op(OPERATOR_COMMA))
1281 error_at(this->location(), "unexpected comma");
1282 if (this->advance_token()->is_op(follow))
1288 // ConstDecl = "const" ( ConstSpec | "(" { ConstSpec ";" } ")" ) .
1293 gcc_assert(this->peek_token()->is_keyword(KEYWORD_CONST));
1294 this->advance_token();
1297 Type* last_type = NULL;
1298 Expression_list* last_expr_list = NULL;
1300 if (!this->peek_token()->is_op(OPERATOR_LPAREN))
1301 this->const_spec(&last_type, &last_expr_list);
1304 this->advance_token();
1305 while (!this->peek_token()->is_op(OPERATOR_RPAREN))
1307 this->const_spec(&last_type, &last_expr_list);
1308 if (this->peek_token()->is_op(OPERATOR_SEMICOLON))
1309 this->advance_token();
1310 else if (!this->peek_token()->is_op(OPERATOR_RPAREN))
1312 error_at(this->location(), "expected %<;%> or %<)%> or newline");
1313 if (!this->skip_past_error(OPERATOR_RPAREN))
1317 this->advance_token();
1320 if (last_expr_list != NULL)
1321 delete last_expr_list;
1324 // ConstSpec = IdentifierList [ [ CompleteType ] "=" ExpressionList ] .
1327 Parse::const_spec(Type** last_type, Expression_list** last_expr_list)
1329 Typed_identifier_list til;
1330 this->identifier_list(&til);
1333 if (this->type_may_start_here())
1335 type = this->type();
1337 *last_expr_list = NULL;
1340 Expression_list *expr_list;
1341 if (!this->peek_token()->is_op(OPERATOR_EQ))
1343 if (*last_expr_list == NULL)
1345 error_at(this->location(), "expected %<=%>");
1349 expr_list = new Expression_list;
1350 for (Expression_list::const_iterator p = (*last_expr_list)->begin();
1351 p != (*last_expr_list)->end();
1353 expr_list->push_back((*p)->copy());
1357 this->advance_token();
1358 expr_list = this->expression_list(NULL, false);
1360 if (*last_expr_list != NULL)
1361 delete *last_expr_list;
1362 *last_expr_list = expr_list;
1365 Expression_list::const_iterator pe = expr_list->begin();
1366 for (Typed_identifier_list::iterator pi = til.begin();
1370 if (pe == expr_list->end())
1372 error_at(this->location(), "not enough initializers");
1378 if (!Gogo::is_sink_name(pi->name()))
1379 this->gogo_->add_constant(*pi, *pe, this->iota_value());
1381 if (pe != expr_list->end())
1382 error_at(this->location(), "too many initializers");
1384 this->increment_iota();
1389 // TypeDecl = "type" Decl<TypeSpec> .
1394 gcc_assert(this->peek_token()->is_keyword(KEYWORD_TYPE));
1395 this->advance_token();
1396 this->decl(&Parse::type_spec, NULL);
1399 // TypeSpec = identifier Type .
1402 Parse::type_spec(void*)
1404 const Token* token = this->peek_token();
1405 if (!token->is_identifier())
1407 error_at(this->location(), "expected identifier");
1410 std::string name = token->identifier();
1411 bool is_exported = token->is_identifier_exported();
1412 source_location location = token->location();
1413 token = this->advance_token();
1415 // The scope of the type name starts at the point where the
1416 // identifier appears in the source code. We implement this by
1417 // declaring the type before we read the type definition.
1418 Named_object* named_type = NULL;
1421 name = this->gogo_->pack_hidden_name(name, is_exported);
1422 named_type = this->gogo_->declare_type(name, location);
1426 if (!this->peek_token()->is_op(OPERATOR_SEMICOLON))
1427 type = this->type();
1430 error_at(this->location(),
1431 "unexpected semicolon or newline in type declaration");
1432 type = Type::make_error_type();
1433 this->advance_token();
1436 if (type->is_error_type())
1438 while (!this->peek_token()->is_op(OPERATOR_SEMICOLON)
1439 && !this->peek_token()->is_eof())
1440 this->advance_token();
1445 if (named_type->is_type_declaration())
1447 Type* ftype = type->forwarded();
1448 if (ftype->forward_declaration_type() != NULL
1449 && (ftype->forward_declaration_type()->named_object()
1452 error_at(location, "invalid recursive type");
1453 type = Type::make_error_type();
1456 this->gogo_->define_type(named_type,
1457 Type::make_named_type(named_type, type,
1459 gcc_assert(named_type->package() == NULL);
1463 // This will probably give a redefinition error.
1464 this->gogo_->add_type(name, type, location);
1469 // VarDecl = "var" Decl<VarSpec> .
1474 gcc_assert(this->peek_token()->is_keyword(KEYWORD_VAR));
1475 this->advance_token();
1476 this->decl(&Parse::var_spec, NULL);
1479 // VarSpec = IdentifierList
1480 // ( CompleteType [ "=" ExpressionList ] | "=" ExpressionList ) .
1483 Parse::var_spec(void*)
1485 // Get the variable names.
1486 Typed_identifier_list til;
1487 this->identifier_list(&til);
1489 source_location location = this->location();
1492 Expression_list* init = NULL;
1493 if (!this->peek_token()->is_op(OPERATOR_EQ))
1495 type = this->type();
1496 if (type->is_error_type())
1498 while (!this->peek_token()->is_op(OPERATOR_EQ)
1499 && !this->peek_token()->is_op(OPERATOR_SEMICOLON)
1500 && !this->peek_token()->is_eof())
1501 this->advance_token();
1503 if (this->peek_token()->is_op(OPERATOR_EQ))
1505 this->advance_token();
1506 init = this->expression_list(NULL, false);
1511 this->advance_token();
1512 init = this->expression_list(NULL, false);
1515 this->init_vars(&til, type, init, false, location);
1521 // Create variables. TIL is a list of variable names. If TYPE is not
1522 // NULL, it is the type of all the variables. If INIT is not NULL, it
1523 // is an initializer list for the variables.
1526 Parse::init_vars(const Typed_identifier_list* til, Type* type,
1527 Expression_list* init, bool is_coloneq,
1528 source_location location)
1530 // Check for an initialization which can yield multiple values.
1531 if (init != NULL && init->size() == 1 && til->size() > 1)
1533 if (this->init_vars_from_call(til, type, *init->begin(), is_coloneq,
1536 if (this->init_vars_from_map(til, type, *init->begin(), is_coloneq,
1539 if (this->init_vars_from_receive(til, type, *init->begin(), is_coloneq,
1542 if (this->init_vars_from_type_guard(til, type, *init->begin(),
1543 is_coloneq, location))
1547 if (init != NULL && init->size() != til->size())
1549 if (init->empty() || !init->front()->is_error_expression())
1550 error_at(location, "wrong number of initializations");
1553 type = Type::make_error_type();
1556 // Note that INIT was already parsed with the old name bindings, so
1557 // we don't have to worry that it will accidentally refer to the
1558 // newly declared variables.
1560 Expression_list::const_iterator pexpr;
1562 pexpr = init->begin();
1563 bool any_new = false;
1564 for (Typed_identifier_list::const_iterator p = til->begin();
1569 gcc_assert(pexpr != init->end());
1570 this->init_var(*p, type, init == NULL ? NULL : *pexpr, is_coloneq,
1576 gcc_assert(pexpr == init->end());
1577 if (is_coloneq && !any_new)
1578 error_at(location, "variables redeclared but no variable is new");
1581 // See if we need to initialize a list of variables from a function
1582 // call. This returns true if we have set up the variables and the
1586 Parse::init_vars_from_call(const Typed_identifier_list* vars, Type* type,
1587 Expression* expr, bool is_coloneq,
1588 source_location location)
1590 Call_expression* call = expr->call_expression();
1594 // This is a function call. We can't check here whether it returns
1595 // the right number of values, but it might. Declare the variables,
1596 // and then assign the results of the call to them.
1598 unsigned int index = 0;
1599 bool any_new = false;
1600 for (Typed_identifier_list::const_iterator pv = vars->begin();
1604 Expression* init = Expression::make_call_result(call, index);
1605 this->init_var(*pv, type, init, is_coloneq, false, &any_new);
1608 if (is_coloneq && !any_new)
1609 error_at(location, "variables redeclared but no variable is new");
1614 // See if we need to initialize a pair of values from a map index
1615 // expression. This returns true if we have set up the variables and
1616 // the initialization.
1619 Parse::init_vars_from_map(const Typed_identifier_list* vars, Type* type,
1620 Expression* expr, bool is_coloneq,
1621 source_location location)
1623 Index_expression* index = expr->index_expression();
1626 if (vars->size() != 2)
1629 // This is an index which is being assigned to two variables. It
1630 // must be a map index. Declare the variables, and then assign the
1631 // results of the map index.
1632 bool any_new = false;
1633 Typed_identifier_list::const_iterator p = vars->begin();
1634 Expression* init = type == NULL ? index : NULL;
1635 Named_object* val_no = this->init_var(*p, type, init, is_coloneq,
1636 type == NULL, &any_new);
1637 if (type == NULL && any_new && val_no->is_variable())
1638 val_no->var_value()->set_type_from_init_tuple();
1639 Expression* val_var = Expression::make_var_reference(val_no, location);
1642 Type* var_type = type;
1643 if (var_type == NULL)
1644 var_type = Type::lookup_bool_type();
1645 Named_object* no = this->init_var(*p, var_type, NULL, is_coloneq, false,
1647 Expression* present_var = Expression::make_var_reference(no, location);
1649 if (is_coloneq && !any_new)
1650 error_at(location, "variables redeclared but no variable is new");
1652 Statement* s = Statement::make_tuple_map_assignment(val_var, present_var,
1655 if (!this->gogo_->in_global_scope())
1656 this->gogo_->add_statement(s);
1657 else if (!val_no->is_sink())
1658 val_no->var_value()->add_preinit_statement(s);
1659 else if (!no->is_sink())
1660 no->var_value()->add_preinit_statement(s);
1663 // Execute the map index expression just so that we can fail if
1665 Named_object* dummy = this->create_dummy_global(Type::lookup_bool_type(),
1667 dummy->var_value()->add_preinit_statement(s);
1673 // See if we need to initialize a pair of values from a receive
1674 // expression. This returns true if we have set up the variables and
1675 // the initialization.
1678 Parse::init_vars_from_receive(const Typed_identifier_list* vars, Type* type,
1679 Expression* expr, bool is_coloneq,
1680 source_location location)
1682 Receive_expression* receive = expr->receive_expression();
1683 if (receive == NULL)
1685 if (vars->size() != 2)
1688 // This is a receive expression which is being assigned to two
1689 // variables. Declare the variables, and then assign the results of
1691 bool any_new = false;
1692 Typed_identifier_list::const_iterator p = vars->begin();
1693 Expression* init = type == NULL ? receive : NULL;
1694 Named_object* val_no = this->init_var(*p, type, init, is_coloneq,
1695 type == NULL, &any_new);
1696 if (type == NULL && any_new && val_no->is_variable())
1697 val_no->var_value()->set_type_from_init_tuple();
1698 Expression* val_var = Expression::make_var_reference(val_no, location);
1701 Type* var_type = type;
1702 if (var_type == NULL)
1703 var_type = Type::lookup_bool_type();
1704 Named_object* no = this->init_var(*p, var_type, NULL, is_coloneq, false,
1706 Expression* received_var = Expression::make_var_reference(no, location);
1708 if (is_coloneq && !any_new)
1709 error_at(location, "variables redeclared but no variable is new");
1711 Statement* s = Statement::make_tuple_receive_assignment(val_var,
1716 if (!this->gogo_->in_global_scope())
1717 this->gogo_->add_statement(s);
1718 else if (!val_no->is_sink())
1719 val_no->var_value()->add_preinit_statement(s);
1720 else if (!no->is_sink())
1721 no->var_value()->add_preinit_statement(s);
1724 Named_object* dummy = this->create_dummy_global(Type::lookup_bool_type(),
1726 dummy->var_value()->add_preinit_statement(s);
1732 // See if we need to initialize a pair of values from a type guard
1733 // expression. This returns true if we have set up the variables and
1734 // the initialization.
1737 Parse::init_vars_from_type_guard(const Typed_identifier_list* vars,
1738 Type* type, Expression* expr,
1739 bool is_coloneq, source_location location)
1741 Type_guard_expression* type_guard = expr->type_guard_expression();
1742 if (type_guard == NULL)
1744 if (vars->size() != 2)
1747 // This is a type guard expression which is being assigned to two
1748 // variables. Declare the variables, and then assign the results of
1750 bool any_new = false;
1751 Typed_identifier_list::const_iterator p = vars->begin();
1752 Type* var_type = type;
1753 if (var_type == NULL)
1754 var_type = type_guard->type();
1755 Named_object* val_no = this->init_var(*p, var_type, NULL, is_coloneq, false,
1757 Expression* val_var = Expression::make_var_reference(val_no, location);
1761 if (var_type == NULL)
1762 var_type = Type::lookup_bool_type();
1763 Named_object* no = this->init_var(*p, var_type, NULL, is_coloneq, false,
1765 Expression* ok_var = Expression::make_var_reference(no, location);
1767 Expression* texpr = type_guard->expr();
1768 Type* t = type_guard->type();
1769 Statement* s = Statement::make_tuple_type_guard_assignment(val_var, ok_var,
1773 if (is_coloneq && !any_new)
1774 error_at(location, "variables redeclared but no variable is new");
1776 if (!this->gogo_->in_global_scope())
1777 this->gogo_->add_statement(s);
1778 else if (!val_no->is_sink())
1779 val_no->var_value()->add_preinit_statement(s);
1780 else if (!no->is_sink())
1781 no->var_value()->add_preinit_statement(s);
1784 Named_object* dummy = this->create_dummy_global(type, NULL, location);
1785 dummy->var_value()->add_preinit_statement(s);
1791 // Create a single variable. If IS_COLONEQ is true, we permit
1792 // redeclarations in the same block, and we set *IS_NEW when we find a
1793 // new variable which is not a redeclaration.
1796 Parse::init_var(const Typed_identifier& tid, Type* type, Expression* init,
1797 bool is_coloneq, bool type_from_init, bool* is_new)
1799 source_location location = tid.location();
1801 if (Gogo::is_sink_name(tid.name()))
1803 if (!type_from_init && init != NULL)
1805 if (!this->gogo_->in_global_scope())
1806 this->gogo_->add_statement(Statement::make_statement(init));
1808 return this->create_dummy_global(type, init, location);
1810 return this->gogo_->add_sink();
1815 Named_object* no = this->gogo_->lookup_in_block(tid.name());
1817 && (no->is_variable() || no->is_result_variable()))
1819 // INIT may be NULL even when IS_COLONEQ is true for cases
1820 // like v, ok := x.(int).
1821 if (!type_from_init && init != NULL)
1823 Expression *v = Expression::make_var_reference(no, location);
1824 Statement *s = Statement::make_assignment(v, init, location);
1825 this->gogo_->add_statement(s);
1831 Variable* var = new Variable(type, init, this->gogo_->in_global_scope(),
1832 false, false, location);
1833 return this->gogo_->add_variable(tid.name(), var);
1836 // Create a dummy global variable to force an initializer to be run in
1837 // the right place. This is used when a sink variable is initialized
1841 Parse::create_dummy_global(Type* type, Expression* init,
1842 source_location location)
1844 Variable* var = new Variable(type, init, true, false, false, location);
1847 snprintf(buf, sizeof buf, "_.%d", count);
1849 return this->gogo_->add_variable(buf, var);
1852 // SimpleVarDecl = identifier ":=" Expression .
1854 // We've already seen the identifier.
1856 // FIXME: We also have to implement
1857 // IdentifierList ":=" ExpressionList
1858 // In order to support both "a, b := 1, 0" and "a, b = 1, 0" we accept
1859 // tuple assignments here as well.
1861 // If P_RANGE_CLAUSE is not NULL, then this will recognize a
1864 // If P_TYPE_SWITCH is not NULL, this will recognize a type switch
1865 // guard (var := expr.("type") using the literal keyword "type").
1868 Parse::simple_var_decl_or_assignment(const std::string& name,
1869 source_location location,
1870 Range_clause* p_range_clause,
1871 Type_switch* p_type_switch)
1873 Typed_identifier_list til;
1874 til.push_back(Typed_identifier(name, NULL, location));
1876 // We've seen one identifier. If we see a comma now, this could be
1878 if (this->peek_token()->is_op(OPERATOR_COMMA))
1880 gcc_assert(p_type_switch == NULL);
1883 const Token* token = this->advance_token();
1884 if (!token->is_identifier())
1887 std::string id = token->identifier();
1888 bool is_id_exported = token->is_identifier_exported();
1889 source_location id_location = token->location();
1891 token = this->advance_token();
1892 if (!token->is_op(OPERATOR_COMMA))
1894 if (token->is_op(OPERATOR_COLONEQ))
1896 id = this->gogo_->pack_hidden_name(id, is_id_exported);
1897 til.push_back(Typed_identifier(id, NULL, location));
1900 this->unget_token(Token::make_identifier_token(id,
1906 id = this->gogo_->pack_hidden_name(id, is_id_exported);
1907 til.push_back(Typed_identifier(id, NULL, location));
1910 // We have a comma separated list of identifiers in TIL. If the
1911 // next token is COLONEQ, then this is a simple var decl, and we
1912 // have the complete list of identifiers. If the next token is
1913 // not COLONEQ, then the only valid parse is a tuple assignment.
1914 // The list of identifiers we have so far is really a list of
1915 // expressions. There are more expressions following.
1917 if (!this->peek_token()->is_op(OPERATOR_COLONEQ))
1919 Expression_list* exprs = new Expression_list;
1920 for (Typed_identifier_list::const_iterator p = til.begin();
1923 exprs->push_back(this->id_to_expression(p->name(),
1926 Expression_list* more_exprs = this->expression_list(NULL, true);
1927 for (Expression_list::const_iterator p = more_exprs->begin();
1928 p != more_exprs->end();
1930 exprs->push_back(*p);
1933 this->tuple_assignment(exprs, p_range_clause);
1938 gcc_assert(this->peek_token()->is_op(OPERATOR_COLONEQ));
1939 const Token* token = this->advance_token();
1941 if (p_range_clause != NULL && token->is_keyword(KEYWORD_RANGE))
1943 this->range_clause_decl(&til, p_range_clause);
1947 Expression_list* init;
1948 if (p_type_switch == NULL)
1949 init = this->expression_list(NULL, false);
1952 bool is_type_switch = false;
1953 Expression* expr = this->expression(PRECEDENCE_NORMAL, false, true,
1957 p_type_switch->found = true;
1958 p_type_switch->name = name;
1959 p_type_switch->location = location;
1960 p_type_switch->expr = expr;
1964 if (!this->peek_token()->is_op(OPERATOR_COMMA))
1966 init = new Expression_list();
1967 init->push_back(expr);
1971 this->advance_token();
1972 init = this->expression_list(expr, false);
1976 this->init_vars(&til, NULL, init, true, location);
1979 // FunctionDecl = "func" identifier Signature [ Block ] .
1980 // MethodDecl = "func" Receiver identifier Signature [ Block ] .
1983 // FunctionDecl = "func" identifier Signature
1984 // __asm__ "(" string_lit ")" .
1985 // This extension means a function whose real name is the identifier
1989 Parse::function_decl()
1991 gcc_assert(this->peek_token()->is_keyword(KEYWORD_FUNC));
1992 source_location location = this->location();
1993 const Token* token = this->advance_token();
1995 Typed_identifier* rec = NULL;
1996 if (token->is_op(OPERATOR_LPAREN))
1998 rec = this->receiver();
1999 token = this->peek_token();
2002 if (!token->is_identifier())
2004 error_at(this->location(), "expected function name");
2009 this->gogo_->pack_hidden_name(token->identifier(),
2010 token->is_identifier_exported());
2012 this->advance_token();
2014 Function_type* fntype = this->signature(rec, this->location());
2018 Named_object* named_object = NULL;
2020 if (this->peek_token()->is_keyword(KEYWORD_ASM))
2022 if (!this->advance_token()->is_op(OPERATOR_LPAREN))
2024 error_at(this->location(), "expected %<(%>");
2027 token = this->advance_token();
2028 if (!token->is_string())
2030 error_at(this->location(), "expected string");
2033 std::string asm_name = token->string_value();
2034 if (!this->advance_token()->is_op(OPERATOR_RPAREN))
2036 error_at(this->location(), "expected %<)%>");
2039 this->advance_token();
2040 named_object = this->gogo_->declare_function(name, fntype, location);
2041 if (named_object->is_function_declaration())
2042 named_object->func_declaration_value()->set_asm_name(asm_name);
2045 // Check for the easy error of a newline before the opening brace.
2046 if (this->peek_token()->is_op(OPERATOR_SEMICOLON))
2048 source_location semi_loc = this->location();
2049 if (this->advance_token()->is_op(OPERATOR_LCURLY))
2050 error_at(this->location(),
2051 "unexpected semicolon or newline before %<{%>");
2053 this->unget_token(Token::make_operator_token(OPERATOR_SEMICOLON,
2057 if (!this->peek_token()->is_op(OPERATOR_LCURLY))
2059 if (named_object == NULL)
2060 named_object = this->gogo_->declare_function(name, fntype, location);
2064 this->gogo_->start_function(name, fntype, true, location);
2065 source_location end_loc = this->block();
2066 this->gogo_->finish_function(end_loc);
2070 // Receiver = "(" [ identifier ] [ "*" ] BaseTypeName ")" .
2071 // BaseTypeName = identifier .
2076 gcc_assert(this->peek_token()->is_op(OPERATOR_LPAREN));
2079 const Token* token = this->advance_token();
2080 source_location location = token->location();
2081 if (!token->is_op(OPERATOR_MULT))
2083 if (!token->is_identifier())
2085 error_at(this->location(), "method has no receiver");
2086 while (!token->is_eof() && !token->is_op(OPERATOR_RPAREN))
2087 token = this->advance_token();
2088 if (!token->is_eof())
2089 this->advance_token();
2092 name = token->identifier();
2093 bool is_exported = token->is_identifier_exported();
2094 token = this->advance_token();
2095 if (!token->is_op(OPERATOR_DOT) && !token->is_op(OPERATOR_RPAREN))
2097 // An identifier followed by something other than a dot or a
2098 // right parenthesis must be a receiver name followed by a
2100 name = this->gogo_->pack_hidden_name(name, is_exported);
2104 // This must be a type name.
2105 this->unget_token(Token::make_identifier_token(name, is_exported,
2107 token = this->peek_token();
2112 // Here the receiver name is in NAME (it is empty if the receiver is
2113 // unnamed) and TOKEN is the first token in the type.
2115 bool is_pointer = false;
2116 if (token->is_op(OPERATOR_MULT))
2119 token = this->advance_token();
2122 if (!token->is_identifier())
2124 error_at(this->location(), "expected receiver name or type");
2125 int c = token->is_op(OPERATOR_LPAREN) ? 1 : 0;
2126 while (!token->is_eof())
2128 token = this->advance_token();
2129 if (token->is_op(OPERATOR_LPAREN))
2131 else if (token->is_op(OPERATOR_RPAREN))
2138 if (!token->is_eof())
2139 this->advance_token();
2143 Type* type = this->type_name(true);
2145 if (is_pointer && !type->is_error_type())
2146 type = Type::make_pointer_type(type);
2148 if (this->peek_token()->is_op(OPERATOR_RPAREN))
2149 this->advance_token();
2152 if (this->peek_token()->is_op(OPERATOR_COMMA))
2153 error_at(this->location(), "method has multiple receivers");
2155 error_at(this->location(), "expected %<)%>");
2156 while (!token->is_eof() && !token->is_op(OPERATOR_RPAREN))
2157 token = this->advance_token();
2158 if (!token->is_eof())
2159 this->advance_token();
2163 return new Typed_identifier(name, type, location);
2166 // Operand = Literal | QualifiedIdent | MethodExpr | "(" Expression ")" .
2167 // Literal = BasicLit | CompositeLit | FunctionLit .
2168 // BasicLit = int_lit | float_lit | imaginary_lit | char_lit | string_lit .
2170 // If MAY_BE_SINK is true, this operand may be "_".
2173 Parse::operand(bool may_be_sink)
2175 const Token* token = this->peek_token();
2177 switch (token->classification())
2179 case Token::TOKEN_IDENTIFIER:
2181 source_location location = token->location();
2182 std::string id = token->identifier();
2183 bool is_exported = token->is_identifier_exported();
2184 std::string packed = this->gogo_->pack_hidden_name(id, is_exported);
2186 Named_object* in_function;
2187 Named_object* named_object = this->gogo_->lookup(packed, &in_function);
2189 Package* package = NULL;
2190 if (named_object != NULL && named_object->is_package())
2192 if (!this->advance_token()->is_op(OPERATOR_DOT)
2193 || !this->advance_token()->is_identifier())
2195 error_at(location, "unexpected reference to package");
2196 return Expression::make_error(location);
2198 package = named_object->package_value();
2199 package->set_used();
2200 id = this->peek_token()->identifier();
2201 is_exported = this->peek_token()->is_identifier_exported();
2202 packed = this->gogo_->pack_hidden_name(id, is_exported);
2203 named_object = package->lookup(packed);
2204 location = this->location();
2205 gcc_assert(in_function == NULL);
2208 this->advance_token();
2210 if (named_object != NULL
2211 && named_object->is_type()
2212 && !named_object->type_value()->is_visible())
2214 gcc_assert(package != NULL);
2215 error_at(location, "invalid reference to hidden type %<%s.%s%>",
2216 Gogo::message_name(package->name()).c_str(),
2217 Gogo::message_name(id).c_str());
2218 return Expression::make_error(location);
2222 if (named_object == NULL)
2224 if (package != NULL)
2226 std::string n1 = Gogo::message_name(package->name());
2227 std::string n2 = Gogo::message_name(id);
2230 ("invalid reference to unexported identifier "
2232 n1.c_str(), n2.c_str());
2235 "reference to undefined identifier %<%s.%s%>",
2236 n1.c_str(), n2.c_str());
2237 return Expression::make_error(location);
2240 named_object = this->gogo_->add_unknown_name(packed, location);
2243 if (in_function != NULL
2244 && in_function != this->gogo_->current_function()
2245 && (named_object->is_variable()
2246 || named_object->is_result_variable()))
2247 return this->enclosing_var_reference(in_function, named_object,
2250 switch (named_object->classification())
2252 case Named_object::NAMED_OBJECT_CONST:
2253 return Expression::make_const_reference(named_object, location);
2254 case Named_object::NAMED_OBJECT_TYPE:
2255 return Expression::make_type(named_object->type_value(), location);
2256 case Named_object::NAMED_OBJECT_TYPE_DECLARATION:
2258 Type* t = Type::make_forward_declaration(named_object);
2259 return Expression::make_type(t, location);
2261 case Named_object::NAMED_OBJECT_VAR:
2262 case Named_object::NAMED_OBJECT_RESULT_VAR:
2263 return Expression::make_var_reference(named_object, location);
2264 case Named_object::NAMED_OBJECT_SINK:
2266 return Expression::make_sink(location);
2269 error_at(location, "cannot use _ as value");
2270 return Expression::make_error(location);
2272 case Named_object::NAMED_OBJECT_FUNC:
2273 case Named_object::NAMED_OBJECT_FUNC_DECLARATION:
2274 return Expression::make_func_reference(named_object, NULL,
2276 case Named_object::NAMED_OBJECT_UNKNOWN:
2277 return Expression::make_unknown_reference(named_object, location);
2284 case Token::TOKEN_STRING:
2285 ret = Expression::make_string(token->string_value(), token->location());
2286 this->advance_token();
2289 case Token::TOKEN_INTEGER:
2290 ret = Expression::make_integer(token->integer_value(), NULL,
2292 this->advance_token();
2295 case Token::TOKEN_FLOAT:
2296 ret = Expression::make_float(token->float_value(), NULL,
2298 this->advance_token();
2301 case Token::TOKEN_IMAGINARY:
2304 mpfr_init_set_ui(zero, 0, GMP_RNDN);
2305 ret = Expression::make_complex(&zero, token->imaginary_value(),
2306 NULL, token->location());
2308 this->advance_token();
2312 case Token::TOKEN_KEYWORD:
2313 switch (token->keyword())
2316 return this->function_lit();
2318 case KEYWORD_INTERFACE:
2320 case KEYWORD_STRUCT:
2322 source_location location = token->location();
2323 return Expression::make_type(this->type(), location);
2330 case Token::TOKEN_OPERATOR:
2331 if (token->is_op(OPERATOR_LPAREN))
2333 this->advance_token();
2334 ret = this->expression(PRECEDENCE_NORMAL, false, true, NULL);
2335 if (!this->peek_token()->is_op(OPERATOR_RPAREN))
2336 error_at(this->location(), "missing %<)%>");
2338 this->advance_token();
2341 else if (token->is_op(OPERATOR_LSQUARE))
2343 // Here we call array_type directly, as this is the only
2344 // case where an ellipsis is permitted for an array type.
2345 source_location location = token->location();
2346 return Expression::make_type(this->array_type(true), location);
2354 error_at(this->location(), "expected operand");
2355 return Expression::make_error(this->location());
2358 // Handle a reference to a variable in an enclosing function. We add
2359 // it to a list of such variables. We return a reference to a field
2360 // in a struct which will be passed on the static chain when calling
2361 // the current function.
2364 Parse::enclosing_var_reference(Named_object* in_function, Named_object* var,
2365 source_location location)
2367 gcc_assert(var->is_variable() || var->is_result_variable());
2369 Named_object* this_function = this->gogo_->current_function();
2370 Named_object* closure = this_function->func_value()->closure_var();
2372 Enclosing_var ev(var, in_function, this->enclosing_vars_.size());
2373 std::pair<Enclosing_vars::iterator, bool> ins =
2374 this->enclosing_vars_.insert(ev);
2377 // This is a variable we have not seen before. Add a new field
2378 // to the closure type.
2379 this_function->func_value()->add_closure_field(var, location);
2382 Expression* closure_ref = Expression::make_var_reference(closure,
2384 closure_ref = Expression::make_unary(OPERATOR_MULT, closure_ref, location);
2386 // The closure structure holds pointers to the variables, so we need
2387 // to introduce an indirection.
2388 Expression* e = Expression::make_field_reference(closure_ref,
2391 e = Expression::make_unary(OPERATOR_MULT, e, location);
2395 // CompositeLit = LiteralType LiteralValue .
2396 // LiteralType = StructType | ArrayType | "[" "..." "]" ElementType |
2397 // SliceType | MapType | TypeName .
2398 // LiteralValue = "{" [ ElementList [ "," ] ] "}" .
2399 // ElementList = Element { "," Element } .
2400 // Element = [ Key ":" ] Value .
2401 // Key = Expression .
2402 // Value = Expression | LiteralValue .
2404 // We have already seen the type if there is one, and we are now
2405 // looking at the LiteralValue. The case "[" "..." "]" ElementType
2406 // will be seen here as an array type whose length is "nil". The
2407 // DEPTH parameter is non-zero if this is an embedded composite
2408 // literal and the type was omitted. It gives the number of steps up
2409 // to the type which was provided. E.g., in [][]int{{1}} it will be
2410 // 1. In [][][]int{{{1}}} it will be 2.
2413 Parse::composite_lit(Type* type, int depth, source_location location)
2415 gcc_assert(this->peek_token()->is_op(OPERATOR_LCURLY));
2416 this->advance_token();
2418 if (this->peek_token()->is_op(OPERATOR_RCURLY))
2420 this->advance_token();
2421 return Expression::make_composite_literal(type, depth, false, NULL,
2425 bool has_keys = false;
2426 Expression_list* vals = new Expression_list;
2430 bool is_type_omitted = false;
2432 const Token* token = this->peek_token();
2434 if (!token->is_op(OPERATOR_LCURLY))
2435 val = this->expression(PRECEDENCE_NORMAL, false, true, NULL);
2438 // This must be a composite literal inside another composite
2439 // literal, with the type omitted for the inner one.
2440 val = this->composite_lit(type, depth + 1, token->location());
2441 is_type_omitted = true;
2444 token = this->peek_token();
2445 if (!token->is_op(OPERATOR_COLON))
2448 vals->push_back(NULL);
2452 if (is_type_omitted && !val->is_error_expression())
2454 error_at(this->location(), "unexpected %<:%>");
2455 val = Expression::make_error(this->location());
2458 this->advance_token();
2460 if (!has_keys && !vals->empty())
2462 Expression_list* newvals = new Expression_list;
2463 for (Expression_list::const_iterator p = vals->begin();
2467 newvals->push_back(NULL);
2468 newvals->push_back(*p);
2475 if (val->unknown_expression() != NULL)
2476 val->unknown_expression()->set_is_composite_literal_key();
2478 vals->push_back(val);
2480 if (!token->is_op(OPERATOR_LCURLY))
2481 val = this->expression(PRECEDENCE_NORMAL, false, true, NULL);
2484 // This must be a composite literal inside another
2485 // composite literal, with the type omitted for the
2487 val = this->composite_lit(type, depth + 1, token->location());
2490 token = this->peek_token();
2493 vals->push_back(val);
2495 if (token->is_op(OPERATOR_COMMA))
2497 if (this->advance_token()->is_op(OPERATOR_RCURLY))
2499 this->advance_token();
2503 else if (token->is_op(OPERATOR_RCURLY))
2505 this->advance_token();
2510 error_at(this->location(), "expected %<,%> or %<}%>");
2513 while (!token->is_eof()
2514 && (depth > 0 || !token->is_op(OPERATOR_RCURLY)))
2516 if (token->is_op(OPERATOR_LCURLY))
2518 else if (token->is_op(OPERATOR_RCURLY))
2520 token = this->advance_token();
2522 if (token->is_op(OPERATOR_RCURLY))
2523 this->advance_token();
2525 return Expression::make_error(location);
2529 return Expression::make_composite_literal(type, depth, has_keys, vals,
2533 // FunctionLit = "func" Signature Block .
2536 Parse::function_lit()
2538 source_location location = this->location();
2539 gcc_assert(this->peek_token()->is_keyword(KEYWORD_FUNC));
2540 this->advance_token();
2542 Enclosing_vars hold_enclosing_vars;
2543 hold_enclosing_vars.swap(this->enclosing_vars_);
2545 Function_type* type = this->signature(NULL, location);
2547 type = Type::make_function_type(NULL, NULL, NULL, location);
2549 // For a function literal, the next token must be a '{'. If we
2550 // don't see that, then we may have a type expression.
2551 if (!this->peek_token()->is_op(OPERATOR_LCURLY))
2552 return Expression::make_type(type, location);
2554 Named_object* no = this->gogo_->start_function("", type, true, location);
2556 source_location end_loc = this->block();
2558 this->gogo_->finish_function(end_loc);
2560 hold_enclosing_vars.swap(this->enclosing_vars_);
2562 Expression* closure = this->create_closure(no, &hold_enclosing_vars,
2565 return Expression::make_func_reference(no, closure, location);
2568 // Create a closure for the nested function FUNCTION. This is based
2569 // on ENCLOSING_VARS, which is a list of all variables defined in
2570 // enclosing functions and referenced from FUNCTION. A closure is the
2571 // address of a struct which contains the addresses of all the
2572 // referenced variables. This returns NULL if no closure is required.
2575 Parse::create_closure(Named_object* function, Enclosing_vars* enclosing_vars,
2576 source_location location)
2578 if (enclosing_vars->empty())
2581 // Get the variables in order by their field index.
2583 size_t enclosing_var_count = enclosing_vars->size();
2584 std::vector<Enclosing_var> ev(enclosing_var_count);
2585 for (Enclosing_vars::const_iterator p = enclosing_vars->begin();
2586 p != enclosing_vars->end();
2588 ev[p->index()] = *p;
2590 // Build an initializer for a composite literal of the closure's
2593 Named_object* enclosing_function = this->gogo_->current_function();
2594 Expression_list* initializer = new Expression_list;
2595 for (size_t i = 0; i < enclosing_var_count; ++i)
2597 gcc_assert(ev[i].index() == i);
2598 Named_object* var = ev[i].var();
2600 if (ev[i].in_function() == enclosing_function)
2601 ref = Expression::make_var_reference(var, location);
2603 ref = this->enclosing_var_reference(ev[i].in_function(), var,
2605 Expression* refaddr = Expression::make_unary(OPERATOR_AND, ref,
2607 initializer->push_back(refaddr);
2610 Named_object* closure_var = function->func_value()->closure_var();
2611 Struct_type* st = closure_var->var_value()->type()->deref()->struct_type();
2612 Expression* cv = Expression::make_struct_composite_literal(st, initializer,
2614 return Expression::make_heap_composite(cv, location);
2617 // PrimaryExpr = Operand { Selector | Index | Slice | TypeGuard | Call } .
2619 // If MAY_BE_SINK is true, this expression may be "_".
2621 // If MAY_BE_COMPOSITE_LIT is true, this expression may be a composite
2624 // If IS_TYPE_SWITCH is not NULL, this will recognize a type switch
2625 // guard (var := expr.("type") using the literal keyword "type").
2628 Parse::primary_expr(bool may_be_sink, bool may_be_composite_lit,
2629 bool* is_type_switch)
2631 source_location start_loc = this->location();
2632 bool is_parenthesized = this->peek_token()->is_op(OPERATOR_LPAREN);
2634 Expression* ret = this->operand(may_be_sink);
2636 // An unknown name followed by a curly brace must be a composite
2637 // literal, and the unknown name must be a type.
2638 if (may_be_composite_lit
2639 && !is_parenthesized
2640 && ret->unknown_expression() != NULL
2641 && this->peek_token()->is_op(OPERATOR_LCURLY))
2643 Named_object* no = ret->unknown_expression()->named_object();
2644 Type* type = Type::make_forward_declaration(no);
2645 ret = Expression::make_type(type, ret->location());
2648 // We handle composite literals and type casts here, as it is the
2649 // easiest way to handle types which are in parentheses, as in
2651 if (ret->is_type_expression())
2653 if (this->peek_token()->is_op(OPERATOR_LCURLY))
2655 if (is_parenthesized)
2657 "cannot parenthesize type in composite literal");
2658 ret = this->composite_lit(ret->type(), 0, ret->location());
2660 else if (this->peek_token()->is_op(OPERATOR_LPAREN))
2662 source_location loc = this->location();
2663 this->advance_token();
2664 Expression* expr = this->expression(PRECEDENCE_NORMAL, false, true,
2666 if (!this->peek_token()->is_op(OPERATOR_RPAREN))
2667 error_at(this->location(), "expected %<)%>");
2669 this->advance_token();
2670 if (expr->is_error_expression())
2672 ret = Expression::make_cast(ret->type(), expr, loc);
2678 const Token* token = this->peek_token();
2679 if (token->is_op(OPERATOR_LPAREN))
2680 ret = this->call(this->verify_not_sink(ret));
2681 else if (token->is_op(OPERATOR_DOT))
2683 ret = this->selector(this->verify_not_sink(ret), is_type_switch);
2684 if (is_type_switch != NULL && *is_type_switch)
2687 else if (token->is_op(OPERATOR_LSQUARE))
2688 ret = this->index(this->verify_not_sink(ret));
2696 // Selector = "." identifier .
2697 // TypeGuard = "." "(" QualifiedIdent ")" .
2699 // Note that Operand can expand to QualifiedIdent, which contains a
2700 // ".". That is handled directly in operand when it sees a package
2703 // If IS_TYPE_SWITCH is not NULL, this will recognize a type switch
2704 // guard (var := expr.("type") using the literal keyword "type").
2707 Parse::selector(Expression* left, bool* is_type_switch)
2709 gcc_assert(this->peek_token()->is_op(OPERATOR_DOT));
2710 source_location location = this->location();
2712 const Token* token = this->advance_token();
2713 if (token->is_identifier())
2715 // This could be a field in a struct, or a method in an
2716 // interface, or a method associated with a type. We can't know
2717 // which until we have seen all the types.
2719 this->gogo_->pack_hidden_name(token->identifier(),
2720 token->is_identifier_exported());
2721 if (token->identifier() == "_")
2723 error_at(this->location(), "invalid use of %<_%>");
2724 name = this->gogo_->pack_hidden_name("blank", false);
2726 this->advance_token();
2727 return Expression::make_selector(left, name, location);
2729 else if (token->is_op(OPERATOR_LPAREN))
2731 this->advance_token();
2733 if (!this->peek_token()->is_keyword(KEYWORD_TYPE))
2734 type = this->type();
2737 if (is_type_switch != NULL)
2738 *is_type_switch = true;
2741 error_at(this->location(),
2742 "use of %<.(type)%> outside type switch");
2743 type = Type::make_error_type();
2745 this->advance_token();
2747 if (!this->peek_token()->is_op(OPERATOR_RPAREN))
2748 error_at(this->location(), "missing %<)%>");
2750 this->advance_token();
2751 if (is_type_switch != NULL && *is_type_switch)
2753 return Expression::make_type_guard(left, type, location);
2757 error_at(this->location(), "expected identifier or %<(%>");
2762 // Index = "[" Expression "]" .
2763 // Slice = "[" Expression ":" [ Expression ] "]" .
2766 Parse::index(Expression* expr)
2768 source_location location = this->location();
2769 gcc_assert(this->peek_token()->is_op(OPERATOR_LSQUARE));
2770 this->advance_token();
2773 if (!this->peek_token()->is_op(OPERATOR_COLON))
2774 start = this->expression(PRECEDENCE_NORMAL, false, true, NULL);
2778 mpz_init_set_ui(zero, 0);
2779 start = Expression::make_integer(&zero, NULL, location);
2783 Expression* end = NULL;
2784 if (this->peek_token()->is_op(OPERATOR_COLON))
2786 // We use nil to indicate a missing high expression.
2787 if (this->advance_token()->is_op(OPERATOR_RSQUARE))
2788 end = Expression::make_nil(this->location());
2790 end = this->expression(PRECEDENCE_NORMAL, false, true, NULL);
2792 if (!this->peek_token()->is_op(OPERATOR_RSQUARE))
2793 error_at(this->location(), "missing %<]%>");
2795 this->advance_token();
2796 return Expression::make_index(expr, start, end, location);
2799 // Call = "(" [ ArgumentList [ "," ] ] ")" .
2800 // ArgumentList = ExpressionList [ "..." ] .
2803 Parse::call(Expression* func)
2805 gcc_assert(this->peek_token()->is_op(OPERATOR_LPAREN));
2806 Expression_list* args = NULL;
2807 bool is_varargs = false;
2808 const Token* token = this->advance_token();
2809 if (!token->is_op(OPERATOR_RPAREN))
2811 args = this->expression_list(NULL, false);
2812 token = this->peek_token();
2813 if (token->is_op(OPERATOR_ELLIPSIS))
2816 token = this->advance_token();
2819 if (token->is_op(OPERATOR_COMMA))
2820 token = this->advance_token();
2821 if (!token->is_op(OPERATOR_RPAREN))
2822 error_at(this->location(), "missing %<)%>");
2824 this->advance_token();
2825 if (func->is_error_expression())
2827 return Expression::make_call(func, args, is_varargs, func->location());
2830 // Return an expression for a single unqualified identifier.
2833 Parse::id_to_expression(const std::string& name, source_location location)
2835 Named_object* in_function;
2836 Named_object* named_object = this->gogo_->lookup(name, &in_function);
2837 if (named_object == NULL)
2838 named_object = this->gogo_->add_unknown_name(name, location);
2840 if (in_function != NULL
2841 && in_function != this->gogo_->current_function()
2842 && (named_object->is_variable() || named_object->is_result_variable()))
2843 return this->enclosing_var_reference(in_function, named_object,
2846 switch (named_object->classification())
2848 case Named_object::NAMED_OBJECT_CONST:
2849 return Expression::make_const_reference(named_object, location);
2850 case Named_object::NAMED_OBJECT_VAR:
2851 case Named_object::NAMED_OBJECT_RESULT_VAR:
2852 return Expression::make_var_reference(named_object, location);
2853 case Named_object::NAMED_OBJECT_SINK:
2854 return Expression::make_sink(location);
2855 case Named_object::NAMED_OBJECT_FUNC:
2856 case Named_object::NAMED_OBJECT_FUNC_DECLARATION:
2857 return Expression::make_func_reference(named_object, NULL, location);
2858 case Named_object::NAMED_OBJECT_UNKNOWN:
2859 return Expression::make_unknown_reference(named_object, location);
2861 error_at(this->location(), "unexpected type of identifier");
2862 return Expression::make_error(location);
2866 // Expression = UnaryExpr { binary_op Expression } .
2868 // PRECEDENCE is the precedence of the current operator.
2870 // If MAY_BE_SINK is true, this expression may be "_".
2872 // If MAY_BE_COMPOSITE_LIT is true, this expression may be a composite
2875 // If IS_TYPE_SWITCH is not NULL, this will recognize a type switch
2876 // guard (var := expr.("type") using the literal keyword "type").
2879 Parse::expression(Precedence precedence, bool may_be_sink,
2880 bool may_be_composite_lit, bool* is_type_switch)
2882 Expression* left = this->unary_expr(may_be_sink, may_be_composite_lit,
2887 if (is_type_switch != NULL && *is_type_switch)
2890 const Token* token = this->peek_token();
2891 if (token->classification() != Token::TOKEN_OPERATOR)
2897 Precedence right_precedence;
2898 switch (token->op())
2901 right_precedence = PRECEDENCE_OROR;
2903 case OPERATOR_ANDAND:
2904 right_precedence = PRECEDENCE_ANDAND;
2906 case OPERATOR_CHANOP:
2907 right_precedence = PRECEDENCE_CHANOP;
2910 case OPERATOR_NOTEQ:
2915 right_precedence = PRECEDENCE_RELOP;
2918 case OPERATOR_MINUS:
2921 right_precedence = PRECEDENCE_ADDOP;
2926 case OPERATOR_LSHIFT:
2927 case OPERATOR_RSHIFT:
2929 case OPERATOR_BITCLEAR:
2930 right_precedence = PRECEDENCE_MULOP;
2933 right_precedence = PRECEDENCE_INVALID;
2937 if (right_precedence == PRECEDENCE_INVALID)
2943 Operator op = token->op();
2944 source_location binop_location = token->location();
2946 if (precedence >= right_precedence)
2948 // We've already seen A * B, and we see + C. We want to
2949 // return so that A * B becomes a group.
2953 this->advance_token();
2955 left = this->verify_not_sink(left);
2956 Expression* right = this->expression(right_precedence, false,
2957 may_be_composite_lit,
2959 if (op == OPERATOR_CHANOP)
2960 left = Expression::make_send(left, right, binop_location);
2962 left = Expression::make_binary(op, left, right, binop_location);
2967 Parse::expression_may_start_here()
2969 const Token* token = this->peek_token();
2970 switch (token->classification())
2972 case Token::TOKEN_INVALID:
2973 case Token::TOKEN_EOF:
2975 case Token::TOKEN_KEYWORD:
2976 switch (token->keyword())
2981 case KEYWORD_STRUCT:
2982 case KEYWORD_INTERFACE:
2987 case Token::TOKEN_IDENTIFIER:
2989 case Token::TOKEN_STRING:
2991 case Token::TOKEN_OPERATOR:
2992 switch (token->op())
2995 case OPERATOR_MINUS:
2999 case OPERATOR_CHANOP:
3001 case OPERATOR_LPAREN:
3002 case OPERATOR_LSQUARE:
3007 case Token::TOKEN_INTEGER:
3008 case Token::TOKEN_FLOAT:
3009 case Token::TOKEN_IMAGINARY:
3016 // UnaryExpr = unary_op UnaryExpr | PrimaryExpr .
3018 // If MAY_BE_SINK is true, this expression may be "_".
3020 // If MAY_BE_COMPOSITE_LIT is true, this expression may be a composite
3023 // If IS_TYPE_SWITCH is not NULL, this will recognize a type switch
3024 // guard (var := expr.("type") using the literal keyword "type").
3027 Parse::unary_expr(bool may_be_sink, bool may_be_composite_lit,
3028 bool* is_type_switch)
3030 const Token* token = this->peek_token();
3031 if (token->is_op(OPERATOR_PLUS)
3032 || token->is_op(OPERATOR_MINUS)
3033 || token->is_op(OPERATOR_NOT)
3034 || token->is_op(OPERATOR_XOR)
3035 || token->is_op(OPERATOR_CHANOP)
3036 || token->is_op(OPERATOR_MULT)
3037 || token->is_op(OPERATOR_AND))
3039 source_location location = token->location();
3040 Operator op = token->op();
3041 this->advance_token();
3043 if (op == OPERATOR_CHANOP
3044 && this->peek_token()->is_keyword(KEYWORD_CHAN))
3046 // This is "<- chan" which must be the start of a type.
3047 this->unget_token(Token::make_operator_token(op, location));
3048 return Expression::make_type(this->type(), location);
3051 Expression* expr = this->unary_expr(false, may_be_composite_lit, NULL);
3052 if (expr->is_error_expression())
3054 else if (op == OPERATOR_MULT && expr->is_type_expression())
3055 expr = Expression::make_type(Type::make_pointer_type(expr->type()),
3057 else if (op == OPERATOR_AND && expr->is_composite_literal())
3058 expr = Expression::make_heap_composite(expr, location);
3059 else if (op != OPERATOR_CHANOP)
3060 expr = Expression::make_unary(op, expr, location);
3062 expr = Expression::make_receive(expr, location);
3066 return this->primary_expr(may_be_sink, may_be_composite_lit,
3071 // Declaration | LabeledStmt | SimpleStmt |
3072 // GoStmt | ReturnStmt | BreakStmt | ContinueStmt | GotoStmt |
3073 // FallthroughStmt | Block | IfStmt | SwitchStmt | SelectStmt | ForStmt |
3076 // LABEL is the label of this statement if it has one.
3079 Parse::statement(const Label* label)
3081 const Token* token = this->peek_token();
3082 switch (token->classification())
3084 case Token::TOKEN_KEYWORD:
3086 switch (token->keyword())
3091 this->declaration();
3095 case KEYWORD_STRUCT:
3096 case KEYWORD_INTERFACE:
3097 this->simple_stat(true, false, NULL, NULL);
3101 this->go_or_defer_stat();
3103 case KEYWORD_RETURN:
3104 this->return_stat();
3109 case KEYWORD_CONTINUE:
3110 this->continue_stat();
3118 case KEYWORD_SWITCH:
3119 this->switch_stat(label);
3121 case KEYWORD_SELECT:
3122 this->select_stat(label);
3125 this->for_stat(label);
3128 error_at(this->location(), "expected statement");
3129 this->advance_token();
3135 case Token::TOKEN_IDENTIFIER:
3137 std::string identifier = token->identifier();
3138 bool is_exported = token->is_identifier_exported();
3139 source_location location = token->location();
3140 if (this->advance_token()->is_op(OPERATOR_COLON))
3142 this->advance_token();
3143 this->labeled_stmt(identifier, location);
3147 this->unget_token(Token::make_identifier_token(identifier,
3150 this->simple_stat(true, false, NULL, NULL);
3155 case Token::TOKEN_OPERATOR:
3156 if (token->is_op(OPERATOR_LCURLY))
3158 source_location location = token->location();
3159 this->gogo_->start_block(location);
3160 source_location end_loc = this->block();
3161 this->gogo_->add_block(this->gogo_->finish_block(end_loc),
3164 else if (!token->is_op(OPERATOR_SEMICOLON))
3165 this->simple_stat(true, false, NULL, NULL);
3168 case Token::TOKEN_STRING:
3169 case Token::TOKEN_INTEGER:
3170 case Token::TOKEN_FLOAT:
3171 case Token::TOKEN_IMAGINARY:
3172 this->simple_stat(true, false, NULL, NULL);
3176 error_at(this->location(), "expected statement");
3177 this->advance_token();
3183 Parse::statement_may_start_here()
3185 const Token* token = this->peek_token();
3186 switch (token->classification())
3188 case Token::TOKEN_KEYWORD:
3190 switch (token->keyword())
3197 case KEYWORD_STRUCT:
3198 case KEYWORD_INTERFACE:
3201 case KEYWORD_RETURN:
3203 case KEYWORD_CONTINUE:
3206 case KEYWORD_SWITCH:
3207 case KEYWORD_SELECT:
3217 case Token::TOKEN_IDENTIFIER:
3220 case Token::TOKEN_OPERATOR:
3221 if (token->is_op(OPERATOR_LCURLY)
3222 || token->is_op(OPERATOR_SEMICOLON))
3225 return this->expression_may_start_here();
3227 case Token::TOKEN_STRING:
3228 case Token::TOKEN_INTEGER:
3229 case Token::TOKEN_FLOAT:
3230 case Token::TOKEN_IMAGINARY:
3238 // LabeledStmt = Label ":" Statement .
3239 // Label = identifier .
3242 Parse::labeled_stmt(const std::string& label_name, source_location location)
3244 Label* label = this->gogo_->add_label_definition(label_name, location);
3246 if (this->peek_token()->is_op(OPERATOR_RCURLY))
3248 // This is a label at the end of a block. A program is
3249 // permitted to omit a semicolon here.
3253 if (!this->statement_may_start_here())
3255 error_at(location, "missing statement after label");
3256 this->unget_token(Token::make_operator_token(OPERATOR_SEMICOLON,
3261 this->statement(label);
3265 // ExpressionStat | IncDecStat | Assignment | SimpleVarDecl .
3267 // In order to make this work for if and switch statements, if
3268 // RETURN_EXP is true, and we see an ExpressionStat, we return the
3269 // expression rather than adding an expression statement to the
3270 // current block. If we see something other than an ExpressionStat,
3271 // we add the statement and return NULL.
3273 // If P_RANGE_CLAUSE is not NULL, then this will recognize a
3276 // If P_TYPE_SWITCH is not NULL, this will recognize a type switch
3277 // guard (var := expr.("type") using the literal keyword "type").
3280 Parse::simple_stat(bool may_be_composite_lit, bool return_exp,
3281 Range_clause* p_range_clause, Type_switch* p_type_switch)
3283 const Token* token = this->peek_token();
3285 // An identifier follow by := is a SimpleVarDecl.
3286 if (token->is_identifier())
3288 std::string identifier = token->identifier();
3289 bool is_exported = token->is_identifier_exported();
3290 source_location location = token->location();
3292 token = this->advance_token();
3293 if (token->is_op(OPERATOR_COLONEQ)
3294 || token->is_op(OPERATOR_COMMA))
3296 identifier = this->gogo_->pack_hidden_name(identifier, is_exported);
3297 this->simple_var_decl_or_assignment(identifier, location,
3299 (token->is_op(OPERATOR_COLONEQ)
3305 this->unget_token(Token::make_identifier_token(identifier, is_exported,
3309 Expression* exp = this->expression(PRECEDENCE_NORMAL, true,
3310 may_be_composite_lit,
3311 (p_type_switch == NULL
3313 : &p_type_switch->found));
3314 if (p_type_switch != NULL && p_type_switch->found)
3316 p_type_switch->name.clear();
3317 p_type_switch->location = exp->location();
3318 p_type_switch->expr = this->verify_not_sink(exp);
3321 token = this->peek_token();
3322 if (token->is_op(OPERATOR_PLUSPLUS) || token->is_op(OPERATOR_MINUSMINUS))
3323 this->inc_dec_stat(this->verify_not_sink(exp));
3324 else if (token->is_op(OPERATOR_COMMA)
3325 || token->is_op(OPERATOR_EQ))
3326 this->assignment(exp, p_range_clause);
3327 else if (token->is_op(OPERATOR_PLUSEQ)
3328 || token->is_op(OPERATOR_MINUSEQ)
3329 || token->is_op(OPERATOR_OREQ)
3330 || token->is_op(OPERATOR_XOREQ)
3331 || token->is_op(OPERATOR_MULTEQ)
3332 || token->is_op(OPERATOR_DIVEQ)
3333 || token->is_op(OPERATOR_MODEQ)
3334 || token->is_op(OPERATOR_LSHIFTEQ)
3335 || token->is_op(OPERATOR_RSHIFTEQ)
3336 || token->is_op(OPERATOR_ANDEQ)
3337 || token->is_op(OPERATOR_BITCLEAREQ))
3338 this->assignment(this->verify_not_sink(exp), p_range_clause);
3339 else if (return_exp)
3340 return this->verify_not_sink(exp);
3342 this->expression_stat(this->verify_not_sink(exp));
3348 Parse::simple_stat_may_start_here()
3350 return this->expression_may_start_here();
3353 // Parse { Statement ";" } which is used in a few places. The list of
3354 // statements may end with a right curly brace, in which case the
3355 // semicolon may be omitted.
3358 Parse::statement_list()
3360 while (this->statement_may_start_here())
3362 this->statement(NULL);
3363 if (this->peek_token()->is_op(OPERATOR_SEMICOLON))
3364 this->advance_token();
3365 else if (this->peek_token()->is_op(OPERATOR_RCURLY))
3369 if (!this->peek_token()->is_eof() || !saw_errors())
3370 error_at(this->location(), "expected %<;%> or %<}%> or newline");
3371 if (!this->skip_past_error(OPERATOR_RCURLY))
3378 Parse::statement_list_may_start_here()
3380 return this->statement_may_start_here();
3383 // ExpressionStat = Expression .
3386 Parse::expression_stat(Expression* exp)
3388 exp->discarding_value();
3389 this->gogo_->add_statement(Statement::make_statement(exp));
3392 // IncDecStat = Expression ( "++" | "--" ) .
3395 Parse::inc_dec_stat(Expression* exp)
3397 const Token* token = this->peek_token();
3399 // Lvalue maps require special handling.
3400 if (exp->index_expression() != NULL)
3401 exp->index_expression()->set_is_lvalue();
3403 if (token->is_op(OPERATOR_PLUSPLUS))
3404 this->gogo_->add_statement(Statement::make_inc_statement(exp));
3405 else if (token->is_op(OPERATOR_MINUSMINUS))
3406 this->gogo_->add_statement(Statement::make_dec_statement(exp));
3409 this->advance_token();
3412 // Assignment = ExpressionList assign_op ExpressionList .
3414 // EXP is an expression that we have already parsed.
3416 // If RANGE_CLAUSE is not NULL, then this will recognize a
3420 Parse::assignment(Expression* expr, Range_clause* p_range_clause)
3422 Expression_list* vars;
3423 if (!this->peek_token()->is_op(OPERATOR_COMMA))
3425 vars = new Expression_list();
3426 vars->push_back(expr);
3430 this->advance_token();
3431 vars = this->expression_list(expr, true);
3434 this->tuple_assignment(vars, p_range_clause);
3437 // An assignment statement. LHS is the list of expressions which
3438 // appear on the left hand side.
3440 // If RANGE_CLAUSE is not NULL, then this will recognize a
3444 Parse::tuple_assignment(Expression_list* lhs, Range_clause* p_range_clause)
3446 const Token* token = this->peek_token();
3447 if (!token->is_op(OPERATOR_EQ)
3448 && !token->is_op(OPERATOR_PLUSEQ)
3449 && !token->is_op(OPERATOR_MINUSEQ)
3450 && !token->is_op(OPERATOR_OREQ)
3451 && !token->is_op(OPERATOR_XOREQ)
3452 && !token->is_op(OPERATOR_MULTEQ)
3453 && !token->is_op(OPERATOR_DIVEQ)
3454 && !token->is_op(OPERATOR_MODEQ)
3455 && !token->is_op(OPERATOR_LSHIFTEQ)
3456 && !token->is_op(OPERATOR_RSHIFTEQ)
3457 && !token->is_op(OPERATOR_ANDEQ)
3458 && !token->is_op(OPERATOR_BITCLEAREQ))
3460 error_at(this->location(), "expected assignment operator");
3463 Operator op = token->op();
3464 source_location location = token->location();
3466 token = this->advance_token();
3468 if (p_range_clause != NULL && token->is_keyword(KEYWORD_RANGE))
3470 if (op != OPERATOR_EQ)
3471 error_at(this->location(), "range clause requires %<=%>");
3472 this->range_clause_expr(lhs, p_range_clause);
3476 Expression_list* vals = this->expression_list(NULL, false);
3478 // We've parsed everything; check for errors.
3479 if (lhs == NULL || vals == NULL)
3481 for (Expression_list::const_iterator pe = lhs->begin();
3485 if ((*pe)->is_error_expression())
3487 if (op != OPERATOR_EQ && (*pe)->is_sink_expression())
3488 error_at((*pe)->location(), "cannot use _ as value");
3490 for (Expression_list::const_iterator pe = vals->begin();
3494 if ((*pe)->is_error_expression())
3498 // Map expressions act differently when they are lvalues.
3499 for (Expression_list::iterator plv = lhs->begin();
3502 if ((*plv)->index_expression() != NULL)
3503 (*plv)->index_expression()->set_is_lvalue();
3505 Call_expression* call;
3506 Index_expression* map_index;
3507 Receive_expression* receive;
3508 Type_guard_expression* type_guard;
3509 if (lhs->size() == vals->size())
3512 if (lhs->size() > 1)
3514 if (op != OPERATOR_EQ)
3515 error_at(location, "multiple values only permitted with %<=%>");
3516 s = Statement::make_tuple_assignment(lhs, vals, location);
3520 if (op == OPERATOR_EQ)
3521 s = Statement::make_assignment(lhs->front(), vals->front(),
3524 s = Statement::make_assignment_operation(op, lhs->front(),
3525 vals->front(), location);
3529 this->gogo_->add_statement(s);
3531 else if (vals->size() == 1
3532 && (call = (*vals->begin())->call_expression()) != NULL)
3534 if (op != OPERATOR_EQ)
3535 error_at(location, "multiple results only permitted with %<=%>");
3537 vals = new Expression_list;
3538 for (unsigned int i = 0; i < lhs->size(); ++i)
3539 vals->push_back(Expression::make_call_result(call, i));
3540 Statement* s = Statement::make_tuple_assignment(lhs, vals, location);
3541 this->gogo_->add_statement(s);
3543 else if (lhs->size() == 2
3544 && vals->size() == 1
3545 && (map_index = (*vals->begin())->index_expression()) != NULL)
3547 if (op != OPERATOR_EQ)
3548 error_at(location, "two values from map requires %<=%>");
3549 Expression* val = lhs->front();
3550 Expression* present = lhs->back();
3551 Statement* s = Statement::make_tuple_map_assignment(val, present,
3552 map_index, location);
3553 this->gogo_->add_statement(s);
3555 else if (lhs->size() == 1
3556 && vals->size() == 2
3557 && (map_index = lhs->front()->index_expression()) != NULL)
3559 if (op != OPERATOR_EQ)
3560 error_at(location, "assigning tuple to map index requires %<=%>");
3561 Expression* val = vals->front();
3562 Expression* should_set = vals->back();
3563 Statement* s = Statement::make_map_assignment(map_index, val, should_set,
3565 this->gogo_->add_statement(s);
3567 else if (lhs->size() == 2
3568 && vals->size() == 1
3569 && (receive = (*vals->begin())->receive_expression()) != NULL)
3571 if (op != OPERATOR_EQ)
3572 error_at(location, "two values from receive requires %<=%>");
3573 Expression* val = lhs->front();
3574 Expression* success = lhs->back();
3575 Expression* channel = receive->channel();
3576 Statement* s = Statement::make_tuple_receive_assignment(val, success,
3579 this->gogo_->add_statement(s);
3581 else if (lhs->size() == 2
3582 && vals->size() == 1
3583 && (type_guard = (*vals->begin())->type_guard_expression()) != NULL)
3585 if (op != OPERATOR_EQ)
3586 error_at(location, "two values from type guard requires %<=%>");
3587 Expression* val = lhs->front();
3588 Expression* ok = lhs->back();
3589 Expression* expr = type_guard->expr();
3590 Type* type = type_guard->type();
3591 Statement* s = Statement::make_tuple_type_guard_assignment(val, ok,
3594 this->gogo_->add_statement(s);
3598 error_at(location, "number of variables does not match number of values");
3602 // GoStat = "go" Expression .
3603 // DeferStat = "defer" Expression .
3606 Parse::go_or_defer_stat()
3608 gcc_assert(this->peek_token()->is_keyword(KEYWORD_GO)
3609 || this->peek_token()->is_keyword(KEYWORD_DEFER));
3610 bool is_go = this->peek_token()->is_keyword(KEYWORD_GO);
3611 source_location stat_location = this->location();
3612 this->advance_token();
3613 source_location expr_location = this->location();
3614 Expression* expr = this->expression(PRECEDENCE_NORMAL, false, true, NULL);
3615 Call_expression* call_expr = expr->call_expression();
3616 if (call_expr == NULL)
3618 error_at(expr_location, "expected call expression");
3622 // Make it easier to simplify go/defer statements by putting every
3623 // statement in its own block.
3624 this->gogo_->start_block(stat_location);
3627 stat = Statement::make_go_statement(call_expr, stat_location);
3629 stat = Statement::make_defer_statement(call_expr, stat_location);
3630 this->gogo_->add_statement(stat);
3631 this->gogo_->add_block(this->gogo_->finish_block(stat_location),
3635 // ReturnStat = "return" [ ExpressionList ] .
3638 Parse::return_stat()
3640 gcc_assert(this->peek_token()->is_keyword(KEYWORD_RETURN));
3641 source_location location = this->location();
3642 this->advance_token();
3643 Expression_list* vals = NULL;
3644 if (this->expression_may_start_here())
3645 vals = this->expression_list(NULL, false);
3646 const Function* function = this->gogo_->current_function()->func_value();
3647 const Typed_identifier_list* results = function->type()->results();
3648 this->gogo_->add_statement(Statement::make_return_statement(results, vals,
3652 // IfStat = "if" [ [ SimpleStat ] ";" ] [ Condition ]
3653 // Block [ "else" Statement ] .
3658 gcc_assert(this->peek_token()->is_keyword(KEYWORD_IF));
3659 source_location location = this->location();
3660 this->advance_token();
3662 this->gogo_->start_block(location);
3664 Expression* cond = NULL;
3665 if (this->simple_stat_may_start_here())
3666 cond = this->simple_stat(false, true, NULL, NULL);
3667 if (cond != NULL && this->peek_token()->is_op(OPERATOR_SEMICOLON))
3669 // The SimpleStat is an expression statement.
3670 this->expression_stat(cond);
3675 if (this->peek_token()->is_op(OPERATOR_SEMICOLON))
3676 this->advance_token();
3677 if (!this->peek_token()->is_op(OPERATOR_LCURLY))
3678 cond = this->expression(PRECEDENCE_NORMAL, false, false, NULL);
3681 this->gogo_->start_block(this->location());
3682 source_location end_loc = this->block();
3683 Block* then_block = this->gogo_->finish_block(end_loc);
3685 // Check for the easy error of a newline before "else".
3686 if (this->peek_token()->is_op(OPERATOR_SEMICOLON))
3688 source_location semi_loc = this->location();
3689 if (this->advance_token()->is_keyword(KEYWORD_ELSE))
3690 error_at(this->location(),
3691 "unexpected semicolon or newline before %<else%>");
3693 this->unget_token(Token::make_operator_token(OPERATOR_SEMICOLON,
3697 Block* else_block = NULL;
3698 if (this->peek_token()->is_keyword(KEYWORD_ELSE))
3700 this->advance_token();
3701 // We create a block to gather the statement.
3702 this->gogo_->start_block(this->location());
3703 this->statement(NULL);
3704 else_block = this->gogo_->finish_block(this->location());
3707 this->gogo_->add_statement(Statement::make_if_statement(cond, then_block,
3711 this->gogo_->add_block(this->gogo_->finish_block(this->location()),
3715 // SwitchStmt = ExprSwitchStmt | TypeSwitchStmt .
3716 // ExprSwitchStmt = "switch" [ [ SimpleStat ] ";" ] [ Expression ]
3717 // "{" { ExprCaseClause } "}" .
3718 // TypeSwitchStmt = "switch" [ [ SimpleStat ] ";" ] TypeSwitchGuard
3719 // "{" { TypeCaseClause } "}" .
3720 // TypeSwitchGuard = [ identifier ":=" ] Expression "." "(" "type" ")" .
3723 Parse::switch_stat(const Label* label)
3725 gcc_assert(this->peek_token()->is_keyword(KEYWORD_SWITCH));
3726 source_location location = this->location();
3727 this->advance_token();
3729 this->gogo_->start_block(location);
3731 Expression* switch_val = NULL;
3732 Type_switch type_switch;
3733 if (this->simple_stat_may_start_here())
3734 switch_val = this->simple_stat(false, true, NULL, &type_switch);
3735 if (switch_val != NULL && this->peek_token()->is_op(OPERATOR_SEMICOLON))
3737 // The SimpleStat is an expression statement.
3738 this->expression_stat(switch_val);
3741 if (switch_val == NULL && !type_switch.found)
3743 if (this->peek_token()->is_op(OPERATOR_SEMICOLON))
3744 this->advance_token();
3745 if (!this->peek_token()->is_op(OPERATOR_LCURLY))
3747 if (this->peek_token()->is_identifier())
3749 const Token* token = this->peek_token();
3750 std::string identifier = token->identifier();
3751 bool is_exported = token->is_identifier_exported();
3752 source_location id_loc = token->location();
3754 token = this->advance_token();
3755 bool is_coloneq = token->is_op(OPERATOR_COLONEQ);
3756 this->unget_token(Token::make_identifier_token(identifier,
3761 // This must be a TypeSwitchGuard.
3762 switch_val = this->simple_stat(false, true, NULL,
3764 if (!type_switch.found
3765 && !switch_val->is_error_expression())
3767 error_at(id_loc, "expected type switch assignment");
3768 switch_val = Expression::make_error(id_loc);
3772 if (switch_val == NULL && !type_switch.found)
3774 switch_val = this->expression(PRECEDENCE_NORMAL, false, false,
3775 &type_switch.found);
3776 if (type_switch.found)
3778 type_switch.name.clear();
3779 type_switch.expr = switch_val;
3780 type_switch.location = switch_val->location();
3786 if (!this->peek_token()->is_op(OPERATOR_LCURLY))
3788 source_location token_loc = this->location();
3789 if (this->peek_token()->is_op(OPERATOR_SEMICOLON)
3790 && this->advance_token()->is_op(OPERATOR_LCURLY))
3791 error_at(token_loc, "unexpected semicolon or newline before %<{%>");
3794 error_at(this->location(), "expected %<{%>");
3795 this->gogo_->add_block(this->gogo_->finish_block(this->location()),
3800 this->advance_token();
3802 Statement* statement;
3803 if (type_switch.found)
3804 statement = this->type_switch_body(label, type_switch, location);
3806 statement = this->expr_switch_body(label, switch_val, location);
3808 if (statement != NULL)
3809 this->gogo_->add_statement(statement);
3811 this->gogo_->add_block(this->gogo_->finish_block(this->location()),
3815 // The body of an expression switch.
3816 // "{" { ExprCaseClause } "}"
3819 Parse::expr_switch_body(const Label* label, Expression* switch_val,
3820 source_location location)
3822 Switch_statement* statement = Statement::make_switch_statement(switch_val,
3825 this->push_break_statement(statement, label);
3827 Case_clauses* case_clauses = new Case_clauses();
3828 while (!this->peek_token()->is_op(OPERATOR_RCURLY))
3830 if (this->peek_token()->is_eof())
3833 error_at(this->location(), "missing %<}%>");
3836 this->expr_case_clause(case_clauses);
3838 this->advance_token();
3840 statement->add_clauses(case_clauses);
3842 this->pop_break_statement();
3847 // ExprCaseClause = ExprSwitchCase ":" [ StatementList ] .
3848 // FallthroughStat = "fallthrough" .
3851 Parse::expr_case_clause(Case_clauses* clauses)
3853 source_location location = this->location();
3855 bool is_default = false;
3856 Expression_list* vals = this->expr_switch_case(&is_default);
3858 if (!this->peek_token()->is_op(OPERATOR_COLON))
3861 error_at(this->location(), "expected %<:%>");
3865 this->advance_token();
3867 Block* statements = NULL;
3868 if (this->statement_list_may_start_here())
3870 this->gogo_->start_block(this->location());
3871 this->statement_list();
3872 statements = this->gogo_->finish_block(this->location());
3875 bool is_fallthrough = false;
3876 if (this->peek_token()->is_keyword(KEYWORD_FALLTHROUGH))
3878 is_fallthrough = true;
3879 if (this->advance_token()->is_op(OPERATOR_SEMICOLON))
3880 this->advance_token();
3883 if (is_default || vals != NULL)
3884 clauses->add(vals, is_default, statements, is_fallthrough, location);
3887 // ExprSwitchCase = "case" ExpressionList | "default" .
3890 Parse::expr_switch_case(bool* is_default)
3892 const Token* token = this->peek_token();
3893 if (token->is_keyword(KEYWORD_CASE))
3895 this->advance_token();
3896 return this->expression_list(NULL, false);
3898 else if (token->is_keyword(KEYWORD_DEFAULT))
3900 this->advance_token();
3907 error_at(this->location(), "expected %<case%> or %<default%>");
3908 if (!token->is_op(OPERATOR_RCURLY))
3909 this->advance_token();
3914 // The body of a type switch.
3915 // "{" { TypeCaseClause } "}" .
3918 Parse::type_switch_body(const Label* label, const Type_switch& type_switch,
3919 source_location location)
3921 Named_object* switch_no = NULL;
3922 if (!type_switch.name.empty())
3924 Variable* switch_var = new Variable(NULL, type_switch.expr, false, false,
3925 false, type_switch.location);
3926 switch_no = this->gogo_->add_variable(type_switch.name, switch_var);
3929 Type_switch_statement* statement =
3930 Statement::make_type_switch_statement(switch_no,
3936 this->push_break_statement(statement, label);
3938 Type_case_clauses* case_clauses = new Type_case_clauses();
3939 while (!this->peek_token()->is_op(OPERATOR_RCURLY))
3941 if (this->peek_token()->is_eof())
3943 error_at(this->location(), "missing %<}%>");
3946 this->type_case_clause(switch_no, case_clauses);
3948 this->advance_token();
3950 statement->add_clauses(case_clauses);
3952 this->pop_break_statement();
3957 // TypeCaseClause = TypeSwitchCase ":" [ StatementList ] .
3960 Parse::type_case_clause(Named_object* switch_no, Type_case_clauses* clauses)
3962 source_location location = this->location();
3964 std::vector<Type*> types;
3965 bool is_default = false;
3966 this->type_switch_case(&types, &is_default);
3968 if (!this->peek_token()->is_op(OPERATOR_COLON))
3969 error_at(this->location(), "expected %<:%>");
3971 this->advance_token();
3973 Block* statements = NULL;
3974 if (this->statement_list_may_start_here())
3976 this->gogo_->start_block(this->location());
3977 if (switch_no != NULL && types.size() == 1)
3979 Type* type = types.front();
3980 Expression* init = Expression::make_var_reference(switch_no,
3982 init = Expression::make_type_guard(init, type, location);
3983 Variable* v = new Variable(type, init, false, false, false,
3985 v->set_is_type_switch_var();
3986 this->gogo_->add_variable(switch_no->name(), v);
3988 this->statement_list();
3989 statements = this->gogo_->finish_block(this->location());
3992 if (this->peek_token()->is_keyword(KEYWORD_FALLTHROUGH))
3994 error_at(this->location(),
3995 "fallthrough is not permitted in a type switch");
3996 if (this->advance_token()->is_op(OPERATOR_SEMICOLON))
3997 this->advance_token();
4002 gcc_assert(types.empty());
4003 clauses->add(NULL, false, true, statements, location);
4005 else if (!types.empty())
4007 for (std::vector<Type*>::const_iterator p = types.begin();
4008 p + 1 != types.end();
4010 clauses->add(*p, true, false, NULL, location);
4011 clauses->add(types.back(), false, false, statements, location);
4014 clauses->add(Type::make_error_type(), false, false, statements, location);
4017 // TypeSwitchCase = "case" type | "default"
4019 // We accept a comma separated list of types.
4022 Parse::type_switch_case(std::vector<Type*>* types, bool* is_default)
4024 const Token* token = this->peek_token();
4025 if (token->is_keyword(KEYWORD_CASE))
4027 this->advance_token();
4030 Type* t = this->type();
4031 if (!t->is_error_type())
4032 types->push_back(t);
4033 if (!this->peek_token()->is_op(OPERATOR_COMMA))
4035 this->advance_token();
4038 else if (token->is_keyword(KEYWORD_DEFAULT))
4040 this->advance_token();
4045 error_at(this->location(), "expected %<case%> or %<default%>");
4046 if (!token->is_op(OPERATOR_RCURLY))
4047 this->advance_token();
4051 // SelectStat = "select" "{" { CommClause } "}" .
4054 Parse::select_stat(const Label* label)
4056 gcc_assert(this->peek_token()->is_keyword(KEYWORD_SELECT));
4057 source_location location = this->location();
4058 const Token* token = this->advance_token();
4060 if (!token->is_op(OPERATOR_LCURLY))
4062 source_location token_loc = token->location();
4063 if (token->is_op(OPERATOR_SEMICOLON)
4064 && this->advance_token()->is_op(OPERATOR_LCURLY))
4065 error_at(token_loc, "unexpected semicolon or newline before %<{%>");
4068 error_at(this->location(), "expected %<{%>");
4072 this->advance_token();
4074 Select_statement* statement = Statement::make_select_statement(location);
4076 this->push_break_statement(statement, label);
4078 Select_clauses* select_clauses = new Select_clauses();
4079 while (!this->peek_token()->is_op(OPERATOR_RCURLY))
4081 if (this->peek_token()->is_eof())
4083 error_at(this->location(), "expected %<}%>");
4086 this->comm_clause(select_clauses);
4089 this->advance_token();
4091 statement->add_clauses(select_clauses);
4093 this->pop_break_statement();
4095 this->gogo_->add_statement(statement);
4098 // CommClause = CommCase [ StatementList ] .
4101 Parse::comm_clause(Select_clauses* clauses)
4103 source_location location = this->location();
4104 bool is_send = false;
4105 Expression* channel = NULL;
4106 Expression* val = NULL;
4107 std::string varname;
4108 bool is_default = false;
4109 bool got_case = this->comm_case(&is_send, &channel, &val, &varname,
4112 Block* statements = NULL;
4113 Named_object* var = NULL;
4114 if (this->peek_token()->is_op(OPERATOR_SEMICOLON))
4115 this->advance_token();
4116 else if (this->statement_list_may_start_here())
4118 this->gogo_->start_block(this->location());
4120 if (!varname.empty())
4122 // FIXME: LOCATION is slightly wrong here.
4123 Variable* v = new Variable(NULL, channel, false, false, false,
4125 v->set_type_from_chan_element();
4126 var = this->gogo_->add_variable(varname, v);
4129 this->statement_list();
4130 statements = this->gogo_->finish_block(this->location());
4134 clauses->add(is_send, channel, val, var, is_default, statements, location);
4137 // CommCase = ( "default" | ( "case" ( SendExpr | RecvExpr) ) ) ":" .
4140 Parse::comm_case(bool* is_send, Expression** channel, Expression** val,
4141 std::string* varname, bool* is_default)
4143 const Token* token = this->peek_token();
4144 if (token->is_keyword(KEYWORD_DEFAULT))
4146 this->advance_token();
4149 else if (token->is_keyword(KEYWORD_CASE))
4151 this->advance_token();
4152 if (!this->send_or_recv_expr(is_send, channel, val, varname))
4157 error_at(this->location(), "expected %<case%> or %<default%>");
4158 if (!token->is_op(OPERATOR_RCURLY))
4159 this->advance_token();
4163 if (!this->peek_token()->is_op(OPERATOR_COLON))
4165 error_at(this->location(), "expected colon");
4169 this->advance_token();
4174 // SendExpr = Expression "<-" Expression .
4175 // RecvExpr = [ Expression ( "=" | ":=" ) ] "<-" Expression .
4178 Parse::send_or_recv_expr(bool* is_send, Expression** channel, Expression** val,
4179 std::string* varname)
4181 const Token* token = this->peek_token();
4182 source_location location = token->location();
4183 if (token->is_identifier())
4185 std::string recv_var = token->identifier();
4186 bool is_var_exported = token->is_identifier_exported();
4187 if (!this->advance_token()->is_op(OPERATOR_COLONEQ))
4188 this->unget_token(Token::make_identifier_token(recv_var,
4193 if (!this->advance_token()->is_op(OPERATOR_CHANOP))
4195 error_at(this->location(), "expected %<<-%>");
4199 *varname = this->gogo_->pack_hidden_name(recv_var, is_var_exported);
4200 this->advance_token();
4201 *channel = this->expression(PRECEDENCE_NORMAL, false, true, NULL);
4206 if (this->peek_token()->is_op(OPERATOR_CHANOP))
4209 this->advance_token();
4210 *channel = this->expression(PRECEDENCE_NORMAL, false, true, NULL);
4214 Expression* left = this->expression(PRECEDENCE_CHANOP, true, true, NULL);
4216 if (this->peek_token()->is_op(OPERATOR_EQ))
4218 if (!this->advance_token()->is_op(OPERATOR_CHANOP))
4220 error_at(this->location(), "missing %<<-%>");
4225 this->advance_token();
4226 *channel = this->expression(PRECEDENCE_NORMAL, false, true, NULL);
4228 else if (this->peek_token()->is_op(OPERATOR_CHANOP))
4231 *channel = this->verify_not_sink(left);
4232 this->advance_token();
4233 *val = this->expression(PRECEDENCE_NORMAL, false, true, NULL);
4237 error_at(this->location(), "expected %<<-%> or %<=%>");
4245 // ForStat = "for" [ Condition | ForClause | RangeClause ] Block .
4246 // Condition = Expression .
4249 Parse::for_stat(const Label* label)
4251 gcc_assert(this->peek_token()->is_keyword(KEYWORD_FOR));
4252 source_location location = this->location();
4253 const Token* token = this->advance_token();
4255 // Open a block to hold any variables defined in the init statement
4256 // of the for statement.
4257 this->gogo_->start_block(location);
4260 Expression* cond = NULL;
4262 Range_clause range_clause;
4264 if (!token->is_op(OPERATOR_LCURLY))
4266 if (token->is_keyword(KEYWORD_VAR))
4268 error_at(this->location(),
4269 "var declaration not allowed in for initializer");
4273 if (token->is_op(OPERATOR_SEMICOLON))
4274 this->for_clause(&cond, &post);
4277 // We might be looking at a Condition, an InitStat, or a
4279 cond = this->simple_stat(false, true, &range_clause, NULL);
4280 if (!this->peek_token()->is_op(OPERATOR_SEMICOLON))
4282 if (cond == NULL && !range_clause.found)
4283 error_at(this->location(), "parse error in for statement");
4287 if (range_clause.found)
4288 error_at(this->location(), "parse error after range clause");
4292 // COND is actually an expression statement for
4293 // InitStat at the start of a ForClause.
4294 this->expression_stat(cond);
4298 this->for_clause(&cond, &post);
4303 // Build the For_statement and note that it is the current target
4304 // for break and continue statements.
4306 For_statement* sfor;
4307 For_range_statement* srange;
4309 if (!range_clause.found)
4311 sfor = Statement::make_for_statement(init, cond, post, location);
4317 srange = Statement::make_for_range_statement(range_clause.index,
4325 this->push_break_statement(s, label);
4326 this->push_continue_statement(s, label);
4328 // Gather the block of statements in the loop and add them to the
4331 this->gogo_->start_block(this->location());
4332 source_location end_loc = this->block();
4333 Block* statements = this->gogo_->finish_block(end_loc);
4336 sfor->add_statements(statements);
4338 srange->add_statements(statements);
4340 // This is no longer the break/continue target.
4341 this->pop_break_statement();
4342 this->pop_continue_statement();
4344 // Add the For_statement to the list of statements, and close out
4345 // the block we started to hold any variables defined in the for
4348 this->gogo_->add_statement(s);
4350 this->gogo_->add_block(this->gogo_->finish_block(this->location()),
4354 // ForClause = [ InitStat ] ";" [ Condition ] ";" [ PostStat ] .
4355 // InitStat = SimpleStat .
4356 // PostStat = SimpleStat .
4358 // We have already read InitStat at this point.
4361 Parse::for_clause(Expression** cond, Block** post)
4363 gcc_assert(this->peek_token()->is_op(OPERATOR_SEMICOLON));
4364 this->advance_token();
4365 if (this->peek_token()->is_op(OPERATOR_SEMICOLON))
4367 else if (this->peek_token()->is_op(OPERATOR_LCURLY))
4369 error_at(this->location(),
4370 "unexpected semicolon or newline before %<{%>");
4376 *cond = this->expression(PRECEDENCE_NORMAL, false, true, NULL);
4377 if (!this->peek_token()->is_op(OPERATOR_SEMICOLON))
4378 error_at(this->location(), "expected semicolon");
4380 this->advance_token();
4382 if (this->peek_token()->is_op(OPERATOR_LCURLY))
4386 this->gogo_->start_block(this->location());
4387 this->simple_stat(false, false, NULL, NULL);
4388 *post = this->gogo_->finish_block(this->location());
4392 // RangeClause = IdentifierList ( "=" | ":=" ) "range" Expression .
4394 // This is the := version. It is called with a list of identifiers.
4397 Parse::range_clause_decl(const Typed_identifier_list* til,
4398 Range_clause* p_range_clause)
4400 gcc_assert(this->peek_token()->is_keyword(KEYWORD_RANGE));
4401 source_location location = this->location();
4403 p_range_clause->found = true;
4405 gcc_assert(til->size() >= 1);
4406 if (til->size() > 2)
4407 error_at(this->location(), "too many variables for range clause");
4409 this->advance_token();
4410 Expression* expr = this->expression(PRECEDENCE_NORMAL, false, false, NULL);
4411 p_range_clause->range = expr;
4413 bool any_new = false;
4415 const Typed_identifier* pti = &til->front();
4416 Named_object* no = this->init_var(*pti, NULL, expr, true, true, &any_new);
4417 if (any_new && no->is_variable())
4418 no->var_value()->set_type_from_range_index();
4419 p_range_clause->index = Expression::make_var_reference(no, location);
4421 if (til->size() == 1)
4422 p_range_clause->value = NULL;
4426 bool is_new = false;
4427 no = this->init_var(*pti, NULL, expr, true, true, &is_new);
4428 if (is_new && no->is_variable())
4429 no->var_value()->set_type_from_range_value();
4432 p_range_clause->value = Expression::make_var_reference(no, location);
4436 error_at(location, "variables redeclared but no variable is new");
4439 // The = version of RangeClause. This is called with a list of
4443 Parse::range_clause_expr(const Expression_list* vals,
4444 Range_clause* p_range_clause)
4446 gcc_assert(this->peek_token()->is_keyword(KEYWORD_RANGE));
4448 p_range_clause->found = true;
4450 gcc_assert(vals->size() >= 1);
4451 if (vals->size() > 2)
4452 error_at(this->location(), "too many variables for range clause");
4454 this->advance_token();
4455 p_range_clause->range = this->expression(PRECEDENCE_NORMAL, false, false,
4458 p_range_clause->index = vals->front();
4459 if (vals->size() == 1)
4460 p_range_clause->value = NULL;
4462 p_range_clause->value = vals->back();
4465 // Push a statement on the break stack.
4468 Parse::push_break_statement(Statement* enclosing, const Label* label)
4470 this->break_stack_.push_back(std::make_pair(enclosing, label));
4473 // Push a statement on the continue stack.
4476 Parse::push_continue_statement(Statement* enclosing, const Label* label)
4478 this->continue_stack_.push_back(std::make_pair(enclosing, label));
4481 // Pop the break stack.
4484 Parse::pop_break_statement()
4486 this->break_stack_.pop_back();
4489 // Pop the continue stack.
4492 Parse::pop_continue_statement()
4494 this->continue_stack_.pop_back();
4497 // Find a break or continue statement given a label name.
4500 Parse::find_bc_statement(const Bc_stack* bc_stack, const std::string& label)
4502 for (Bc_stack::const_reverse_iterator p = bc_stack->rbegin();
4503 p != bc_stack->rend();
4505 if (p->second != NULL && p->second->name() == label)
4510 // BreakStat = "break" [ identifier ] .
4515 gcc_assert(this->peek_token()->is_keyword(KEYWORD_BREAK));
4516 source_location location = this->location();
4518 const Token* token = this->advance_token();
4519 Statement* enclosing;
4520 if (!token->is_identifier())
4522 if (this->break_stack_.empty())
4524 error_at(this->location(),
4525 "break statement not within for or switch or select");
4528 enclosing = this->break_stack_.back().first;
4532 enclosing = this->find_bc_statement(&this->break_stack_,
4533 token->identifier());
4534 if (enclosing == NULL)
4536 error_at(token->location(),
4537 ("break label %qs not associated with "
4538 "for or switch or select"),
4539 Gogo::message_name(token->identifier()).c_str());
4540 this->advance_token();
4543 this->advance_token();
4546 Unnamed_label* label;
4547 if (enclosing->classification() == Statement::STATEMENT_FOR)
4548 label = enclosing->for_statement()->break_label();
4549 else if (enclosing->classification() == Statement::STATEMENT_FOR_RANGE)
4550 label = enclosing->for_range_statement()->break_label();
4551 else if (enclosing->classification() == Statement::STATEMENT_SWITCH)
4552 label = enclosing->switch_statement()->break_label();
4553 else if (enclosing->classification() == Statement::STATEMENT_TYPE_SWITCH)
4554 label = enclosing->type_switch_statement()->break_label();
4555 else if (enclosing->classification() == Statement::STATEMENT_SELECT)
4556 label = enclosing->select_statement()->break_label();
4560 this->gogo_->add_statement(Statement::make_break_statement(label,
4564 // ContinueStat = "continue" [ identifier ] .
4567 Parse::continue_stat()
4569 gcc_assert(this->peek_token()->is_keyword(KEYWORD_CONTINUE));
4570 source_location location = this->location();
4572 const Token* token = this->advance_token();
4573 Statement* enclosing;
4574 if (!token->is_identifier())
4576 if (this->continue_stack_.empty())
4578 error_at(this->location(), "continue statement not within for");
4581 enclosing = this->continue_stack_.back().first;
4585 enclosing = this->find_bc_statement(&this->continue_stack_,
4586 token->identifier());
4587 if (enclosing == NULL)
4589 error_at(token->location(),
4590 "continue label %qs not associated with for",
4591 Gogo::message_name(token->identifier()).c_str());
4592 this->advance_token();
4595 this->advance_token();
4598 Unnamed_label* label;
4599 if (enclosing->classification() == Statement::STATEMENT_FOR)
4600 label = enclosing->for_statement()->continue_label();
4601 else if (enclosing->classification() == Statement::STATEMENT_FOR_RANGE)
4602 label = enclosing->for_range_statement()->continue_label();
4606 this->gogo_->add_statement(Statement::make_continue_statement(label,
4610 // GotoStat = "goto" identifier .
4615 gcc_assert(this->peek_token()->is_keyword(KEYWORD_GOTO));
4616 source_location location = this->location();
4617 const Token* token = this->advance_token();
4618 if (!token->is_identifier())
4619 error_at(this->location(), "expected label for goto");
4622 Label* label = this->gogo_->add_label_reference(token->identifier());
4623 Statement* s = Statement::make_goto_statement(label, location);
4624 this->gogo_->add_statement(s);
4625 this->advance_token();
4629 // PackageClause = "package" PackageName .
4632 Parse::package_clause()
4634 const Token* token = this->peek_token();
4635 source_location location = token->location();
4637 if (!token->is_keyword(KEYWORD_PACKAGE))
4639 error_at(this->location(), "program must start with package clause");
4644 token = this->advance_token();
4645 if (token->is_identifier())
4647 name = token->identifier();
4650 error_at(this->location(), "invalid package name _");
4653 this->advance_token();
4657 error_at(this->location(), "package name must be an identifier");
4661 this->gogo_->set_package_name(name, location);
4664 // ImportDecl = "import" Decl<ImportSpec> .
4667 Parse::import_decl()
4669 gcc_assert(this->peek_token()->is_keyword(KEYWORD_IMPORT));
4670 this->advance_token();
4671 this->decl(&Parse::import_spec, NULL);
4674 // ImportSpec = [ "." | PackageName ] PackageFileName .
4677 Parse::import_spec(void*)
4679 const Token* token = this->peek_token();
4680 source_location location = token->location();
4682 std::string local_name;
4683 bool is_local_name_exported = false;
4684 if (token->is_op(OPERATOR_DOT))
4687 token = this->advance_token();
4689 else if (token->is_identifier())
4691 local_name = token->identifier();
4692 is_local_name_exported = token->is_identifier_exported();
4693 token = this->advance_token();
4696 if (!token->is_string())
4698 error_at(this->location(), "missing import package name");
4702 this->gogo_->import_package(token->string_value(), local_name,
4703 is_local_name_exported, location);
4705 this->advance_token();
4708 // SourceFile = PackageClause ";" { ImportDecl ";" }
4709 // { TopLevelDecl ";" } .
4714 this->package_clause();
4716 const Token* token = this->peek_token();
4717 if (token->is_op(OPERATOR_SEMICOLON))
4718 token = this->advance_token();
4720 error_at(this->location(),
4721 "expected %<;%> or newline after package clause");
4723 while (token->is_keyword(KEYWORD_IMPORT))
4725 this->import_decl();
4726 token = this->peek_token();
4727 if (token->is_op(OPERATOR_SEMICOLON))
4728 token = this->advance_token();
4730 error_at(this->location(),
4731 "expected %<;%> or newline after import declaration");
4734 while (!token->is_eof())
4736 if (this->declaration_may_start_here())
4737 this->declaration();
4740 error_at(this->location(), "expected declaration");
4742 this->advance_token();
4743 while (!this->peek_token()->is_eof()
4744 && !this->peek_token()->is_op(OPERATOR_SEMICOLON)
4745 && !this->peek_token()->is_op(OPERATOR_RCURLY));
4746 if (!this->peek_token()->is_eof()
4747 && !this->peek_token()->is_op(OPERATOR_SEMICOLON))
4748 this->advance_token();
4750 token = this->peek_token();
4751 if (token->is_op(OPERATOR_SEMICOLON))
4752 token = this->advance_token();
4753 else if (!token->is_eof() || !saw_errors())
4755 error_at(this->location(),
4756 "expected %<;%> or newline after top level declaration");
4757 this->skip_past_error(OPERATOR_INVALID);
4762 // Reset the current iota value.
4770 // Return the current iota value.
4778 // Increment the current iota value.
4781 Parse::increment_iota()
4786 // Skip forward to a semicolon or OP. OP will normally be
4787 // OPERATOR_RPAREN or OPERATOR_RCURLY. If we find a semicolon, move
4788 // past it and return. If we find OP, it will be the next token to
4789 // read. Return true if we are OK, false if we found EOF.
4792 Parse::skip_past_error(Operator op)
4794 const Token* token = this->peek_token();
4795 while (!token->is_op(op))
4797 if (token->is_eof())
4799 if (token->is_op(OPERATOR_SEMICOLON))
4801 this->advance_token();
4804 token = this->advance_token();
4809 // Check that an expression is not a sink.
4812 Parse::verify_not_sink(Expression* expr)
4814 if (expr->is_sink_expression())
4816 error_at(expr->location(), "cannot use _ as value");
4817 expr = Expression::make_error(expr->location());