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);
1658 val_no->var_value()->add_preinit_statement(s);
1663 // See if we need to initialize a pair of values from a receive
1664 // expression. This returns true if we have set up the variables and
1665 // the initialization.
1668 Parse::init_vars_from_receive(const Typed_identifier_list* vars, Type* type,
1669 Expression* expr, bool is_coloneq,
1670 source_location location)
1672 Receive_expression* receive = expr->receive_expression();
1673 if (receive == NULL)
1675 if (vars->size() != 2)
1678 // This is a receive expression which is being assigned to two
1679 // variables. Declare the variables, and then assign the results of
1681 bool any_new = false;
1682 Typed_identifier_list::const_iterator p = vars->begin();
1683 Expression* init = type == NULL ? receive : NULL;
1684 Named_object* val_no = this->init_var(*p, type, init, is_coloneq,
1685 type == NULL, &any_new);
1686 if (type == NULL && any_new && val_no->is_variable())
1687 val_no->var_value()->set_type_from_init_tuple();
1688 Expression* val_var = Expression::make_var_reference(val_no, location);
1691 Type* var_type = type;
1692 if (var_type == NULL)
1693 var_type = Type::lookup_bool_type();
1694 Named_object* no = this->init_var(*p, var_type, NULL, is_coloneq, false,
1696 Expression* received_var = Expression::make_var_reference(no, location);
1698 if (is_coloneq && !any_new)
1699 error_at(location, "variables redeclared but no variable is new");
1701 Statement* s = Statement::make_tuple_receive_assignment(val_var,
1706 if (!this->gogo_->in_global_scope())
1707 this->gogo_->add_statement(s);
1709 val_no->var_value()->add_preinit_statement(s);
1714 // See if we need to initialize a pair of values from a type guard
1715 // expression. This returns true if we have set up the variables and
1716 // the initialization.
1719 Parse::init_vars_from_type_guard(const Typed_identifier_list* vars,
1720 Type* type, Expression* expr,
1721 bool is_coloneq, source_location location)
1723 Type_guard_expression* type_guard = expr->type_guard_expression();
1724 if (type_guard == NULL)
1726 if (vars->size() != 2)
1729 // This is a type guard expression which is being assigned to two
1730 // variables. Declare the variables, and then assign the results of
1732 bool any_new = false;
1733 Typed_identifier_list::const_iterator p = vars->begin();
1734 Type* var_type = type;
1735 if (var_type == NULL)
1736 var_type = type_guard->type();
1737 Named_object* val_no = this->init_var(*p, var_type, NULL, is_coloneq, false,
1739 Expression* val_var = Expression::make_var_reference(val_no, location);
1743 if (var_type == NULL)
1744 var_type = Type::lookup_bool_type();
1745 Named_object* no = this->init_var(*p, var_type, NULL, is_coloneq, false,
1747 Expression* ok_var = Expression::make_var_reference(no, location);
1749 Expression* texpr = type_guard->expr();
1750 Type* t = type_guard->type();
1751 Statement* s = Statement::make_tuple_type_guard_assignment(val_var, ok_var,
1755 if (is_coloneq && !any_new)
1756 error_at(location, "variables redeclared but no variable is new");
1758 if (!this->gogo_->in_global_scope())
1759 this->gogo_->add_statement(s);
1761 val_no->var_value()->add_preinit_statement(s);
1766 // Create a single variable. If IS_COLONEQ is true, we permit
1767 // redeclarations in the same block, and we set *IS_NEW when we find a
1768 // new variable which is not a redeclaration.
1771 Parse::init_var(const Typed_identifier& tid, Type* type, Expression* init,
1772 bool is_coloneq, bool type_from_init, bool* is_new)
1774 source_location location = tid.location();
1776 if (Gogo::is_sink_name(tid.name()))
1778 if (!type_from_init && init != NULL)
1780 if (!this->gogo_->in_global_scope())
1781 this->gogo_->add_statement(Statement::make_statement(init));
1784 // Create a dummy global variable to force the
1785 // initializer to be run in the right place.
1786 Variable* var = new Variable(type, init, true, false, false,
1790 snprintf(buf, sizeof buf, "_.%d", count);
1792 return this->gogo_->add_variable(buf, var);
1795 return this->gogo_->add_sink();
1800 Named_object* no = this->gogo_->lookup_in_block(tid.name());
1802 && (no->is_variable() || no->is_result_variable()))
1804 // INIT may be NULL even when IS_COLONEQ is true for cases
1805 // like v, ok := x.(int).
1806 if (!type_from_init && init != NULL)
1808 Expression *v = Expression::make_var_reference(no, location);
1809 Statement *s = Statement::make_assignment(v, init, location);
1810 this->gogo_->add_statement(s);
1816 Variable* var = new Variable(type, init, this->gogo_->in_global_scope(),
1817 false, false, location);
1818 return this->gogo_->add_variable(tid.name(), var);
1821 // SimpleVarDecl = identifier ":=" Expression .
1823 // We've already seen the identifier.
1825 // FIXME: We also have to implement
1826 // IdentifierList ":=" ExpressionList
1827 // In order to support both "a, b := 1, 0" and "a, b = 1, 0" we accept
1828 // tuple assignments here as well.
1830 // If P_RANGE_CLAUSE is not NULL, then this will recognize a
1833 // If P_TYPE_SWITCH is not NULL, this will recognize a type switch
1834 // guard (var := expr.("type") using the literal keyword "type").
1837 Parse::simple_var_decl_or_assignment(const std::string& name,
1838 source_location location,
1839 Range_clause* p_range_clause,
1840 Type_switch* p_type_switch)
1842 Typed_identifier_list til;
1843 til.push_back(Typed_identifier(name, NULL, location));
1845 // We've seen one identifier. If we see a comma now, this could be
1847 if (this->peek_token()->is_op(OPERATOR_COMMA))
1849 gcc_assert(p_type_switch == NULL);
1852 const Token* token = this->advance_token();
1853 if (!token->is_identifier())
1856 std::string id = token->identifier();
1857 bool is_id_exported = token->is_identifier_exported();
1858 source_location id_location = token->location();
1860 token = this->advance_token();
1861 if (!token->is_op(OPERATOR_COMMA))
1863 if (token->is_op(OPERATOR_COLONEQ))
1865 id = this->gogo_->pack_hidden_name(id, is_id_exported);
1866 til.push_back(Typed_identifier(id, NULL, location));
1869 this->unget_token(Token::make_identifier_token(id,
1875 id = this->gogo_->pack_hidden_name(id, is_id_exported);
1876 til.push_back(Typed_identifier(id, NULL, location));
1879 // We have a comma separated list of identifiers in TIL. If the
1880 // next token is COLONEQ, then this is a simple var decl, and we
1881 // have the complete list of identifiers. If the next token is
1882 // not COLONEQ, then the only valid parse is a tuple assignment.
1883 // The list of identifiers we have so far is really a list of
1884 // expressions. There are more expressions following.
1886 if (!this->peek_token()->is_op(OPERATOR_COLONEQ))
1888 Expression_list* exprs = new Expression_list;
1889 for (Typed_identifier_list::const_iterator p = til.begin();
1892 exprs->push_back(this->id_to_expression(p->name(),
1895 Expression_list* more_exprs = this->expression_list(NULL, true);
1896 for (Expression_list::const_iterator p = more_exprs->begin();
1897 p != more_exprs->end();
1899 exprs->push_back(*p);
1902 this->tuple_assignment(exprs, p_range_clause);
1907 gcc_assert(this->peek_token()->is_op(OPERATOR_COLONEQ));
1908 const Token* token = this->advance_token();
1910 if (p_range_clause != NULL && token->is_keyword(KEYWORD_RANGE))
1912 this->range_clause_decl(&til, p_range_clause);
1916 Expression_list* init;
1917 if (p_type_switch == NULL)
1918 init = this->expression_list(NULL, false);
1921 bool is_type_switch = false;
1922 Expression* expr = this->expression(PRECEDENCE_NORMAL, false, true,
1926 p_type_switch->found = true;
1927 p_type_switch->name = name;
1928 p_type_switch->location = location;
1929 p_type_switch->expr = expr;
1933 if (!this->peek_token()->is_op(OPERATOR_COMMA))
1935 init = new Expression_list();
1936 init->push_back(expr);
1940 this->advance_token();
1941 init = this->expression_list(expr, false);
1945 this->init_vars(&til, NULL, init, true, location);
1948 // FunctionDecl = "func" identifier Signature [ Block ] .
1949 // MethodDecl = "func" Receiver identifier Signature [ Block ] .
1952 // FunctionDecl = "func" identifier Signature
1953 // __asm__ "(" string_lit ")" .
1954 // This extension means a function whose real name is the identifier
1958 Parse::function_decl()
1960 gcc_assert(this->peek_token()->is_keyword(KEYWORD_FUNC));
1961 source_location location = this->location();
1962 const Token* token = this->advance_token();
1964 Typed_identifier* rec = NULL;
1965 if (token->is_op(OPERATOR_LPAREN))
1967 rec = this->receiver();
1968 token = this->peek_token();
1971 if (!token->is_identifier())
1973 error_at(this->location(), "expected function name");
1978 this->gogo_->pack_hidden_name(token->identifier(),
1979 token->is_identifier_exported());
1981 this->advance_token();
1983 Function_type* fntype = this->signature(rec, this->location());
1987 Named_object* named_object = NULL;
1989 if (this->peek_token()->is_keyword(KEYWORD_ASM))
1991 if (!this->advance_token()->is_op(OPERATOR_LPAREN))
1993 error_at(this->location(), "expected %<(%>");
1996 token = this->advance_token();
1997 if (!token->is_string())
1999 error_at(this->location(), "expected string");
2002 std::string asm_name = token->string_value();
2003 if (!this->advance_token()->is_op(OPERATOR_RPAREN))
2005 error_at(this->location(), "expected %<)%>");
2008 this->advance_token();
2009 named_object = this->gogo_->declare_function(name, fntype, location);
2010 if (named_object->is_function_declaration())
2011 named_object->func_declaration_value()->set_asm_name(asm_name);
2014 // Check for the easy error of a newline before the opening brace.
2015 if (this->peek_token()->is_op(OPERATOR_SEMICOLON))
2017 source_location semi_loc = this->location();
2018 if (this->advance_token()->is_op(OPERATOR_LCURLY))
2019 error_at(this->location(),
2020 "unexpected semicolon or newline before %<{%>");
2022 this->unget_token(Token::make_operator_token(OPERATOR_SEMICOLON,
2026 if (!this->peek_token()->is_op(OPERATOR_LCURLY))
2028 if (named_object == NULL)
2029 named_object = this->gogo_->declare_function(name, fntype, location);
2033 this->gogo_->start_function(name, fntype, true, location);
2034 source_location end_loc = this->block();
2035 this->gogo_->finish_function(end_loc);
2039 // Receiver = "(" [ identifier ] [ "*" ] BaseTypeName ")" .
2040 // BaseTypeName = identifier .
2045 gcc_assert(this->peek_token()->is_op(OPERATOR_LPAREN));
2048 const Token* token = this->advance_token();
2049 source_location location = token->location();
2050 if (!token->is_op(OPERATOR_MULT))
2052 if (!token->is_identifier())
2054 error_at(this->location(), "method has no receiver");
2055 while (!token->is_eof() && !token->is_op(OPERATOR_RPAREN))
2056 token = this->advance_token();
2057 if (!token->is_eof())
2058 this->advance_token();
2061 name = token->identifier();
2062 bool is_exported = token->is_identifier_exported();
2063 token = this->advance_token();
2064 if (!token->is_op(OPERATOR_DOT) && !token->is_op(OPERATOR_RPAREN))
2066 // An identifier followed by something other than a dot or a
2067 // right parenthesis must be a receiver name followed by a
2069 name = this->gogo_->pack_hidden_name(name, is_exported);
2073 // This must be a type name.
2074 this->unget_token(Token::make_identifier_token(name, is_exported,
2076 token = this->peek_token();
2081 // Here the receiver name is in NAME (it is empty if the receiver is
2082 // unnamed) and TOKEN is the first token in the type.
2084 bool is_pointer = false;
2085 if (token->is_op(OPERATOR_MULT))
2088 token = this->advance_token();
2091 if (!token->is_identifier())
2093 error_at(this->location(), "expected receiver name or type");
2094 int c = token->is_op(OPERATOR_LPAREN) ? 1 : 0;
2095 while (!token->is_eof())
2097 token = this->advance_token();
2098 if (token->is_op(OPERATOR_LPAREN))
2100 else if (token->is_op(OPERATOR_RPAREN))
2107 if (!token->is_eof())
2108 this->advance_token();
2112 Type* type = this->type_name(true);
2114 if (is_pointer && !type->is_error_type())
2115 type = Type::make_pointer_type(type);
2117 if (this->peek_token()->is_op(OPERATOR_RPAREN))
2118 this->advance_token();
2121 if (this->peek_token()->is_op(OPERATOR_COMMA))
2122 error_at(this->location(), "method has multiple receivers");
2124 error_at(this->location(), "expected %<)%>");
2125 while (!token->is_eof() && !token->is_op(OPERATOR_RPAREN))
2126 token = this->advance_token();
2127 if (!token->is_eof())
2128 this->advance_token();
2132 return new Typed_identifier(name, type, location);
2135 // Operand = Literal | QualifiedIdent | MethodExpr | "(" Expression ")" .
2136 // Literal = BasicLit | CompositeLit | FunctionLit .
2137 // BasicLit = int_lit | float_lit | imaginary_lit | char_lit | string_lit .
2139 // If MAY_BE_SINK is true, this operand may be "_".
2142 Parse::operand(bool may_be_sink)
2144 const Token* token = this->peek_token();
2146 switch (token->classification())
2148 case Token::TOKEN_IDENTIFIER:
2150 source_location location = token->location();
2151 std::string id = token->identifier();
2152 bool is_exported = token->is_identifier_exported();
2153 std::string packed = this->gogo_->pack_hidden_name(id, is_exported);
2155 Named_object* in_function;
2156 Named_object* named_object = this->gogo_->lookup(packed, &in_function);
2158 Package* package = NULL;
2159 if (named_object != NULL && named_object->is_package())
2161 if (!this->advance_token()->is_op(OPERATOR_DOT)
2162 || !this->advance_token()->is_identifier())
2164 error_at(location, "unexpected reference to package");
2165 return Expression::make_error(location);
2167 package = named_object->package_value();
2168 package->set_used();
2169 id = this->peek_token()->identifier();
2170 is_exported = this->peek_token()->is_identifier_exported();
2171 packed = this->gogo_->pack_hidden_name(id, is_exported);
2172 named_object = package->lookup(packed);
2173 location = this->location();
2174 gcc_assert(in_function == NULL);
2177 this->advance_token();
2179 if (named_object != NULL
2180 && named_object->is_type()
2181 && !named_object->type_value()->is_visible())
2183 gcc_assert(package != NULL);
2184 error_at(location, "invalid reference to hidden type %<%s.%s%>",
2185 Gogo::message_name(package->name()).c_str(),
2186 Gogo::message_name(id).c_str());
2187 return Expression::make_error(location);
2191 if (named_object == NULL)
2193 if (package != NULL)
2195 std::string n1 = Gogo::message_name(package->name());
2196 std::string n2 = Gogo::message_name(id);
2199 ("invalid reference to unexported identifier "
2201 n1.c_str(), n2.c_str());
2204 "reference to undefined identifier %<%s.%s%>",
2205 n1.c_str(), n2.c_str());
2206 return Expression::make_error(location);
2209 named_object = this->gogo_->add_unknown_name(packed, location);
2212 if (in_function != NULL
2213 && in_function != this->gogo_->current_function()
2214 && (named_object->is_variable()
2215 || named_object->is_result_variable()))
2216 return this->enclosing_var_reference(in_function, named_object,
2219 switch (named_object->classification())
2221 case Named_object::NAMED_OBJECT_CONST:
2222 return Expression::make_const_reference(named_object, location);
2223 case Named_object::NAMED_OBJECT_TYPE:
2224 return Expression::make_type(named_object->type_value(), location);
2225 case Named_object::NAMED_OBJECT_TYPE_DECLARATION:
2227 Type* t = Type::make_forward_declaration(named_object);
2228 return Expression::make_type(t, location);
2230 case Named_object::NAMED_OBJECT_VAR:
2231 case Named_object::NAMED_OBJECT_RESULT_VAR:
2232 return Expression::make_var_reference(named_object, location);
2233 case Named_object::NAMED_OBJECT_SINK:
2235 return Expression::make_sink(location);
2238 error_at(location, "cannot use _ as value");
2239 return Expression::make_error(location);
2241 case Named_object::NAMED_OBJECT_FUNC:
2242 case Named_object::NAMED_OBJECT_FUNC_DECLARATION:
2243 return Expression::make_func_reference(named_object, NULL,
2245 case Named_object::NAMED_OBJECT_UNKNOWN:
2246 return Expression::make_unknown_reference(named_object, location);
2253 case Token::TOKEN_STRING:
2254 ret = Expression::make_string(token->string_value(), token->location());
2255 this->advance_token();
2258 case Token::TOKEN_INTEGER:
2259 ret = Expression::make_integer(token->integer_value(), NULL,
2261 this->advance_token();
2264 case Token::TOKEN_FLOAT:
2265 ret = Expression::make_float(token->float_value(), NULL,
2267 this->advance_token();
2270 case Token::TOKEN_IMAGINARY:
2273 mpfr_init_set_ui(zero, 0, GMP_RNDN);
2274 ret = Expression::make_complex(&zero, token->imaginary_value(),
2275 NULL, token->location());
2277 this->advance_token();
2281 case Token::TOKEN_KEYWORD:
2282 switch (token->keyword())
2285 return this->function_lit();
2287 case KEYWORD_INTERFACE:
2289 case KEYWORD_STRUCT:
2291 source_location location = token->location();
2292 return Expression::make_type(this->type(), location);
2299 case Token::TOKEN_OPERATOR:
2300 if (token->is_op(OPERATOR_LPAREN))
2302 this->advance_token();
2303 ret = this->expression(PRECEDENCE_NORMAL, false, true, NULL);
2304 if (!this->peek_token()->is_op(OPERATOR_RPAREN))
2305 error_at(this->location(), "missing %<)%>");
2307 this->advance_token();
2310 else if (token->is_op(OPERATOR_LSQUARE))
2312 // Here we call array_type directly, as this is the only
2313 // case where an ellipsis is permitted for an array type.
2314 source_location location = token->location();
2315 return Expression::make_type(this->array_type(true), location);
2323 error_at(this->location(), "expected operand");
2324 return Expression::make_error(this->location());
2327 // Handle a reference to a variable in an enclosing function. We add
2328 // it to a list of such variables. We return a reference to a field
2329 // in a struct which will be passed on the static chain when calling
2330 // the current function.
2333 Parse::enclosing_var_reference(Named_object* in_function, Named_object* var,
2334 source_location location)
2336 gcc_assert(var->is_variable() || var->is_result_variable());
2338 Named_object* this_function = this->gogo_->current_function();
2339 Named_object* closure = this_function->func_value()->closure_var();
2341 Enclosing_var ev(var, in_function, this->enclosing_vars_.size());
2342 std::pair<Enclosing_vars::iterator, bool> ins =
2343 this->enclosing_vars_.insert(ev);
2346 // This is a variable we have not seen before. Add a new field
2347 // to the closure type.
2348 this_function->func_value()->add_closure_field(var, location);
2351 Expression* closure_ref = Expression::make_var_reference(closure,
2353 closure_ref = Expression::make_unary(OPERATOR_MULT, closure_ref, location);
2355 // The closure structure holds pointers to the variables, so we need
2356 // to introduce an indirection.
2357 Expression* e = Expression::make_field_reference(closure_ref,
2360 e = Expression::make_unary(OPERATOR_MULT, e, location);
2364 // CompositeLit = LiteralType LiteralValue .
2365 // LiteralType = StructType | ArrayType | "[" "..." "]" ElementType |
2366 // SliceType | MapType | TypeName .
2367 // LiteralValue = "{" [ ElementList [ "," ] ] "}" .
2368 // ElementList = Element { "," Element } .
2369 // Element = [ Key ":" ] Value .
2370 // Key = Expression .
2371 // Value = Expression | LiteralValue .
2373 // We have already seen the type if there is one, and we are now
2374 // looking at the LiteralValue. The case "[" "..." "]" ElementType
2375 // will be seen here as an array type whose length is "nil". The
2376 // DEPTH parameter is non-zero if this is an embedded composite
2377 // literal and the type was omitted. It gives the number of steps up
2378 // to the type which was provided. E.g., in [][]int{{1}} it will be
2379 // 1. In [][][]int{{{1}}} it will be 2.
2382 Parse::composite_lit(Type* type, int depth, source_location location)
2384 gcc_assert(this->peek_token()->is_op(OPERATOR_LCURLY));
2385 this->advance_token();
2387 if (this->peek_token()->is_op(OPERATOR_RCURLY))
2389 this->advance_token();
2390 return Expression::make_composite_literal(type, depth, false, NULL,
2394 bool has_keys = false;
2395 Expression_list* vals = new Expression_list;
2399 bool is_type_omitted = false;
2401 const Token* token = this->peek_token();
2403 if (!token->is_op(OPERATOR_LCURLY))
2404 val = this->expression(PRECEDENCE_NORMAL, false, true, NULL);
2407 // This must be a composite literal inside another composite
2408 // literal, with the type omitted for the inner one.
2409 val = this->composite_lit(type, depth + 1, token->location());
2410 is_type_omitted = true;
2413 token = this->peek_token();
2414 if (!token->is_op(OPERATOR_COLON))
2417 vals->push_back(NULL);
2421 if (is_type_omitted && !val->is_error_expression())
2423 error_at(this->location(), "unexpected %<:%>");
2424 val = Expression::make_error(this->location());
2427 this->advance_token();
2429 if (!has_keys && !vals->empty())
2431 Expression_list* newvals = new Expression_list;
2432 for (Expression_list::const_iterator p = vals->begin();
2436 newvals->push_back(NULL);
2437 newvals->push_back(*p);
2444 if (val->unknown_expression() != NULL)
2445 val->unknown_expression()->set_is_composite_literal_key();
2447 vals->push_back(val);
2449 if (!token->is_op(OPERATOR_LCURLY))
2450 val = this->expression(PRECEDENCE_NORMAL, false, true, NULL);
2453 // This must be a composite literal inside another
2454 // composite literal, with the type omitted for the
2456 val = this->composite_lit(type, depth + 1, token->location());
2459 token = this->peek_token();
2462 vals->push_back(val);
2464 if (token->is_op(OPERATOR_COMMA))
2466 if (this->advance_token()->is_op(OPERATOR_RCURLY))
2468 this->advance_token();
2472 else if (token->is_op(OPERATOR_RCURLY))
2474 this->advance_token();
2479 error_at(this->location(), "expected %<,%> or %<}%>");
2482 while (!token->is_eof()
2483 && (depth > 0 || !token->is_op(OPERATOR_RCURLY)))
2485 if (token->is_op(OPERATOR_LCURLY))
2487 else if (token->is_op(OPERATOR_RCURLY))
2489 token = this->advance_token();
2491 if (token->is_op(OPERATOR_RCURLY))
2492 this->advance_token();
2494 return Expression::make_error(location);
2498 return Expression::make_composite_literal(type, depth, has_keys, vals,
2502 // FunctionLit = "func" Signature Block .
2505 Parse::function_lit()
2507 source_location location = this->location();
2508 gcc_assert(this->peek_token()->is_keyword(KEYWORD_FUNC));
2509 this->advance_token();
2511 Enclosing_vars hold_enclosing_vars;
2512 hold_enclosing_vars.swap(this->enclosing_vars_);
2514 Function_type* type = this->signature(NULL, location);
2518 return Expression::make_error(location);
2521 // For a function literal, the next token must be a '{'. If we
2522 // don't see that, then we may have a type expression.
2523 if (!this->peek_token()->is_op(OPERATOR_LCURLY))
2524 return Expression::make_type(type, location);
2526 Named_object* no = this->gogo_->start_function("", type, true, location);
2528 source_location end_loc = this->block();
2530 this->gogo_->finish_function(end_loc);
2532 hold_enclosing_vars.swap(this->enclosing_vars_);
2534 Expression* closure = this->create_closure(no, &hold_enclosing_vars,
2537 return Expression::make_func_reference(no, closure, location);
2540 // Create a closure for the nested function FUNCTION. This is based
2541 // on ENCLOSING_VARS, which is a list of all variables defined in
2542 // enclosing functions and referenced from FUNCTION. A closure is the
2543 // address of a struct which contains the addresses of all the
2544 // referenced variables. This returns NULL if no closure is required.
2547 Parse::create_closure(Named_object* function, Enclosing_vars* enclosing_vars,
2548 source_location location)
2550 if (enclosing_vars->empty())
2553 // Get the variables in order by their field index.
2555 size_t enclosing_var_count = enclosing_vars->size();
2556 std::vector<Enclosing_var> ev(enclosing_var_count);
2557 for (Enclosing_vars::const_iterator p = enclosing_vars->begin();
2558 p != enclosing_vars->end();
2560 ev[p->index()] = *p;
2562 // Build an initializer for a composite literal of the closure's
2565 Named_object* enclosing_function = this->gogo_->current_function();
2566 Expression_list* initializer = new Expression_list;
2567 for (size_t i = 0; i < enclosing_var_count; ++i)
2569 gcc_assert(ev[i].index() == i);
2570 Named_object* var = ev[i].var();
2572 if (ev[i].in_function() == enclosing_function)
2573 ref = Expression::make_var_reference(var, location);
2575 ref = this->enclosing_var_reference(ev[i].in_function(), var,
2577 Expression* refaddr = Expression::make_unary(OPERATOR_AND, ref,
2579 initializer->push_back(refaddr);
2582 Named_object* closure_var = function->func_value()->closure_var();
2583 Struct_type* st = closure_var->var_value()->type()->deref()->struct_type();
2584 Expression* cv = Expression::make_struct_composite_literal(st, initializer,
2586 return Expression::make_heap_composite(cv, location);
2589 // PrimaryExpr = Operand { Selector | Index | Slice | TypeGuard | Call } .
2591 // If MAY_BE_SINK is true, this expression may be "_".
2593 // If MAY_BE_COMPOSITE_LIT is true, this expression may be a composite
2596 // If IS_TYPE_SWITCH is not NULL, this will recognize a type switch
2597 // guard (var := expr.("type") using the literal keyword "type").
2600 Parse::primary_expr(bool may_be_sink, bool may_be_composite_lit,
2601 bool* is_type_switch)
2603 source_location start_loc = this->location();
2604 bool is_parenthesized = this->peek_token()->is_op(OPERATOR_LPAREN);
2606 Expression* ret = this->operand(may_be_sink);
2608 // An unknown name followed by a curly brace must be a composite
2609 // literal, and the unknown name must be a type.
2610 if (may_be_composite_lit
2611 && !is_parenthesized
2612 && ret->unknown_expression() != NULL
2613 && this->peek_token()->is_op(OPERATOR_LCURLY))
2615 Named_object* no = ret->unknown_expression()->named_object();
2616 Type* type = Type::make_forward_declaration(no);
2617 ret = Expression::make_type(type, ret->location());
2620 // We handle composite literals and type casts here, as it is the
2621 // easiest way to handle types which are in parentheses, as in
2623 if (ret->is_type_expression())
2625 if (this->peek_token()->is_op(OPERATOR_LCURLY))
2627 if (is_parenthesized)
2629 "cannot parenthesize type in composite literal");
2630 ret = this->composite_lit(ret->type(), 0, ret->location());
2632 else if (this->peek_token()->is_op(OPERATOR_LPAREN))
2634 source_location loc = this->location();
2635 this->advance_token();
2636 Expression* expr = this->expression(PRECEDENCE_NORMAL, false, true,
2638 if (!this->peek_token()->is_op(OPERATOR_RPAREN))
2639 error_at(this->location(), "expected %<)%>");
2641 this->advance_token();
2642 if (expr->is_error_expression())
2644 ret = Expression::make_cast(ret->type(), expr, loc);
2650 const Token* token = this->peek_token();
2651 if (token->is_op(OPERATOR_LPAREN))
2652 ret = this->call(this->verify_not_sink(ret));
2653 else if (token->is_op(OPERATOR_DOT))
2655 ret = this->selector(this->verify_not_sink(ret), is_type_switch);
2656 if (is_type_switch != NULL && *is_type_switch)
2659 else if (token->is_op(OPERATOR_LSQUARE))
2660 ret = this->index(this->verify_not_sink(ret));
2668 // Selector = "." identifier .
2669 // TypeGuard = "." "(" QualifiedIdent ")" .
2671 // Note that Operand can expand to QualifiedIdent, which contains a
2672 // ".". That is handled directly in operand when it sees a package
2675 // If IS_TYPE_SWITCH is not NULL, this will recognize a type switch
2676 // guard (var := expr.("type") using the literal keyword "type").
2679 Parse::selector(Expression* left, bool* is_type_switch)
2681 gcc_assert(this->peek_token()->is_op(OPERATOR_DOT));
2682 source_location location = this->location();
2684 const Token* token = this->advance_token();
2685 if (token->is_identifier())
2687 // This could be a field in a struct, or a method in an
2688 // interface, or a method associated with a type. We can't know
2689 // which until we have seen all the types.
2691 this->gogo_->pack_hidden_name(token->identifier(),
2692 token->is_identifier_exported());
2693 if (token->identifier() == "_")
2695 error_at(this->location(), "invalid use of %<_%>");
2696 name = this->gogo_->pack_hidden_name("blank", false);
2698 this->advance_token();
2699 return Expression::make_selector(left, name, location);
2701 else if (token->is_op(OPERATOR_LPAREN))
2703 this->advance_token();
2705 if (!this->peek_token()->is_keyword(KEYWORD_TYPE))
2706 type = this->type();
2709 if (is_type_switch != NULL)
2710 *is_type_switch = true;
2713 error_at(this->location(),
2714 "use of %<.(type)%> outside type switch");
2715 type = Type::make_error_type();
2717 this->advance_token();
2719 if (!this->peek_token()->is_op(OPERATOR_RPAREN))
2720 error_at(this->location(), "missing %<)%>");
2722 this->advance_token();
2723 if (is_type_switch != NULL && *is_type_switch)
2725 return Expression::make_type_guard(left, type, location);
2729 error_at(this->location(), "expected identifier or %<(%>");
2734 // Index = "[" Expression "]" .
2735 // Slice = "[" Expression ":" [ Expression ] "]" .
2738 Parse::index(Expression* expr)
2740 source_location location = this->location();
2741 gcc_assert(this->peek_token()->is_op(OPERATOR_LSQUARE));
2742 this->advance_token();
2745 if (!this->peek_token()->is_op(OPERATOR_COLON))
2746 start = this->expression(PRECEDENCE_NORMAL, false, true, NULL);
2750 mpz_init_set_ui(zero, 0);
2751 start = Expression::make_integer(&zero, NULL, location);
2755 Expression* end = NULL;
2756 if (this->peek_token()->is_op(OPERATOR_COLON))
2758 // We use nil to indicate a missing high expression.
2759 if (this->advance_token()->is_op(OPERATOR_RSQUARE))
2760 end = Expression::make_nil(this->location());
2762 end = this->expression(PRECEDENCE_NORMAL, false, true, NULL);
2764 if (!this->peek_token()->is_op(OPERATOR_RSQUARE))
2765 error_at(this->location(), "missing %<]%>");
2767 this->advance_token();
2768 return Expression::make_index(expr, start, end, location);
2771 // Call = "(" [ ArgumentList [ "," ] ] ")" .
2772 // ArgumentList = ExpressionList [ "..." ] .
2775 Parse::call(Expression* func)
2777 gcc_assert(this->peek_token()->is_op(OPERATOR_LPAREN));
2778 Expression_list* args = NULL;
2779 bool is_varargs = false;
2780 const Token* token = this->advance_token();
2781 if (!token->is_op(OPERATOR_RPAREN))
2783 args = this->expression_list(NULL, false);
2784 token = this->peek_token();
2785 if (token->is_op(OPERATOR_ELLIPSIS))
2788 token = this->advance_token();
2791 if (token->is_op(OPERATOR_COMMA))
2792 token = this->advance_token();
2793 if (!token->is_op(OPERATOR_RPAREN))
2794 error_at(this->location(), "missing %<)%>");
2796 this->advance_token();
2797 if (func->is_error_expression())
2799 return Expression::make_call(func, args, is_varargs, func->location());
2802 // Return an expression for a single unqualified identifier.
2805 Parse::id_to_expression(const std::string& name, source_location location)
2807 Named_object* in_function;
2808 Named_object* named_object = this->gogo_->lookup(name, &in_function);
2809 if (named_object == NULL)
2810 named_object = this->gogo_->add_unknown_name(name, location);
2812 if (in_function != NULL
2813 && in_function != this->gogo_->current_function()
2814 && (named_object->is_variable() || named_object->is_result_variable()))
2815 return this->enclosing_var_reference(in_function, named_object,
2818 switch (named_object->classification())
2820 case Named_object::NAMED_OBJECT_CONST:
2821 return Expression::make_const_reference(named_object, location);
2822 case Named_object::NAMED_OBJECT_VAR:
2823 case Named_object::NAMED_OBJECT_RESULT_VAR:
2824 return Expression::make_var_reference(named_object, location);
2825 case Named_object::NAMED_OBJECT_SINK:
2826 return Expression::make_sink(location);
2827 case Named_object::NAMED_OBJECT_FUNC:
2828 case Named_object::NAMED_OBJECT_FUNC_DECLARATION:
2829 return Expression::make_func_reference(named_object, NULL, location);
2830 case Named_object::NAMED_OBJECT_UNKNOWN:
2831 return Expression::make_unknown_reference(named_object, location);
2833 error_at(this->location(), "unexpected type of identifier");
2834 return Expression::make_error(location);
2838 // Expression = UnaryExpr { binary_op Expression } .
2840 // PRECEDENCE is the precedence of the current operator.
2842 // If MAY_BE_SINK is true, this expression may be "_".
2844 // If MAY_BE_COMPOSITE_LIT is true, this expression may be a composite
2847 // If IS_TYPE_SWITCH is not NULL, this will recognize a type switch
2848 // guard (var := expr.("type") using the literal keyword "type").
2851 Parse::expression(Precedence precedence, bool may_be_sink,
2852 bool may_be_composite_lit, bool* is_type_switch)
2854 Expression* left = this->unary_expr(may_be_sink, may_be_composite_lit,
2859 if (is_type_switch != NULL && *is_type_switch)
2862 const Token* token = this->peek_token();
2863 if (token->classification() != Token::TOKEN_OPERATOR)
2869 Precedence right_precedence;
2870 switch (token->op())
2873 right_precedence = PRECEDENCE_OROR;
2875 case OPERATOR_ANDAND:
2876 right_precedence = PRECEDENCE_ANDAND;
2878 case OPERATOR_CHANOP:
2879 right_precedence = PRECEDENCE_CHANOP;
2882 case OPERATOR_NOTEQ:
2887 right_precedence = PRECEDENCE_RELOP;
2890 case OPERATOR_MINUS:
2893 right_precedence = PRECEDENCE_ADDOP;
2898 case OPERATOR_LSHIFT:
2899 case OPERATOR_RSHIFT:
2901 case OPERATOR_BITCLEAR:
2902 right_precedence = PRECEDENCE_MULOP;
2905 right_precedence = PRECEDENCE_INVALID;
2909 if (right_precedence == PRECEDENCE_INVALID)
2915 Operator op = token->op();
2916 source_location binop_location = token->location();
2918 if (precedence >= right_precedence)
2920 // We've already seen A * B, and we see + C. We want to
2921 // return so that A * B becomes a group.
2925 this->advance_token();
2927 left = this->verify_not_sink(left);
2928 Expression* right = this->expression(right_precedence, false,
2929 may_be_composite_lit,
2931 if (op == OPERATOR_CHANOP)
2932 left = Expression::make_send(left, right, binop_location);
2934 left = Expression::make_binary(op, left, right, binop_location);
2939 Parse::expression_may_start_here()
2941 const Token* token = this->peek_token();
2942 switch (token->classification())
2944 case Token::TOKEN_INVALID:
2945 case Token::TOKEN_EOF:
2947 case Token::TOKEN_KEYWORD:
2948 switch (token->keyword())
2953 case KEYWORD_STRUCT:
2954 case KEYWORD_INTERFACE:
2959 case Token::TOKEN_IDENTIFIER:
2961 case Token::TOKEN_STRING:
2963 case Token::TOKEN_OPERATOR:
2964 switch (token->op())
2967 case OPERATOR_MINUS:
2971 case OPERATOR_CHANOP:
2973 case OPERATOR_LPAREN:
2974 case OPERATOR_LSQUARE:
2979 case Token::TOKEN_INTEGER:
2980 case Token::TOKEN_FLOAT:
2981 case Token::TOKEN_IMAGINARY:
2988 // UnaryExpr = unary_op UnaryExpr | PrimaryExpr .
2990 // If MAY_BE_SINK is true, this expression may be "_".
2992 // If MAY_BE_COMPOSITE_LIT is true, this expression may be a composite
2995 // If IS_TYPE_SWITCH is not NULL, this will recognize a type switch
2996 // guard (var := expr.("type") using the literal keyword "type").
2999 Parse::unary_expr(bool may_be_sink, bool may_be_composite_lit,
3000 bool* is_type_switch)
3002 const Token* token = this->peek_token();
3003 if (token->is_op(OPERATOR_PLUS)
3004 || token->is_op(OPERATOR_MINUS)
3005 || token->is_op(OPERATOR_NOT)
3006 || token->is_op(OPERATOR_XOR)
3007 || token->is_op(OPERATOR_CHANOP)
3008 || token->is_op(OPERATOR_MULT)
3009 || token->is_op(OPERATOR_AND))
3011 source_location location = token->location();
3012 Operator op = token->op();
3013 this->advance_token();
3015 if (op == OPERATOR_CHANOP
3016 && this->peek_token()->is_keyword(KEYWORD_CHAN))
3018 // This is "<- chan" which must be the start of a type.
3019 this->unget_token(Token::make_operator_token(op, location));
3020 return Expression::make_type(this->type(), location);
3023 Expression* expr = this->unary_expr(false, may_be_composite_lit, NULL);
3024 if (expr->is_error_expression())
3026 else if (op == OPERATOR_MULT && expr->is_type_expression())
3027 expr = Expression::make_type(Type::make_pointer_type(expr->type()),
3029 else if (op == OPERATOR_AND && expr->is_composite_literal())
3030 expr = Expression::make_heap_composite(expr, location);
3031 else if (op != OPERATOR_CHANOP)
3032 expr = Expression::make_unary(op, expr, location);
3034 expr = Expression::make_receive(expr, location);
3038 return this->primary_expr(may_be_sink, may_be_composite_lit,
3043 // Declaration | LabeledStmt | SimpleStmt |
3044 // GoStmt | ReturnStmt | BreakStmt | ContinueStmt | GotoStmt |
3045 // FallthroughStmt | Block | IfStmt | SwitchStmt | SelectStmt | ForStmt |
3048 // LABEL is the label of this statement if it has one.
3051 Parse::statement(const Label* label)
3053 const Token* token = this->peek_token();
3054 switch (token->classification())
3056 case Token::TOKEN_KEYWORD:
3058 switch (token->keyword())
3063 this->declaration();
3067 case KEYWORD_STRUCT:
3068 case KEYWORD_INTERFACE:
3069 this->simple_stat(true, false, NULL, NULL);
3073 this->go_or_defer_stat();
3075 case KEYWORD_RETURN:
3076 this->return_stat();
3081 case KEYWORD_CONTINUE:
3082 this->continue_stat();
3090 case KEYWORD_SWITCH:
3091 this->switch_stat(label);
3093 case KEYWORD_SELECT:
3094 this->select_stat(label);
3097 this->for_stat(label);
3100 error_at(this->location(), "expected statement");
3101 this->advance_token();
3107 case Token::TOKEN_IDENTIFIER:
3109 std::string identifier = token->identifier();
3110 bool is_exported = token->is_identifier_exported();
3111 source_location location = token->location();
3112 if (this->advance_token()->is_op(OPERATOR_COLON))
3114 this->advance_token();
3115 this->labeled_stmt(identifier, location);
3119 this->unget_token(Token::make_identifier_token(identifier,
3122 this->simple_stat(true, false, NULL, NULL);
3127 case Token::TOKEN_OPERATOR:
3128 if (token->is_op(OPERATOR_LCURLY))
3130 source_location location = token->location();
3131 this->gogo_->start_block(location);
3132 source_location end_loc = this->block();
3133 this->gogo_->add_block(this->gogo_->finish_block(end_loc),
3136 else if (!token->is_op(OPERATOR_SEMICOLON))
3137 this->simple_stat(true, false, NULL, NULL);
3140 case Token::TOKEN_STRING:
3141 case Token::TOKEN_INTEGER:
3142 case Token::TOKEN_FLOAT:
3143 case Token::TOKEN_IMAGINARY:
3144 this->simple_stat(true, false, NULL, NULL);
3148 error_at(this->location(), "expected statement");
3149 this->advance_token();
3155 Parse::statement_may_start_here()
3157 const Token* token = this->peek_token();
3158 switch (token->classification())
3160 case Token::TOKEN_KEYWORD:
3162 switch (token->keyword())
3169 case KEYWORD_STRUCT:
3170 case KEYWORD_INTERFACE:
3173 case KEYWORD_RETURN:
3175 case KEYWORD_CONTINUE:
3178 case KEYWORD_SWITCH:
3179 case KEYWORD_SELECT:
3189 case Token::TOKEN_IDENTIFIER:
3192 case Token::TOKEN_OPERATOR:
3193 if (token->is_op(OPERATOR_LCURLY)
3194 || token->is_op(OPERATOR_SEMICOLON))
3197 return this->expression_may_start_here();
3199 case Token::TOKEN_STRING:
3200 case Token::TOKEN_INTEGER:
3201 case Token::TOKEN_FLOAT:
3202 case Token::TOKEN_IMAGINARY:
3210 // LabeledStmt = Label ":" Statement .
3211 // Label = identifier .
3214 Parse::labeled_stmt(const std::string& label_name, source_location location)
3216 Label* label = this->gogo_->add_label_definition(label_name, location);
3218 if (this->peek_token()->is_op(OPERATOR_RCURLY))
3220 // This is a label at the end of a block. A program is
3221 // permitted to omit a semicolon here.
3225 if (!this->statement_may_start_here())
3227 error_at(location, "missing statement after label");
3228 this->unget_token(Token::make_operator_token(OPERATOR_SEMICOLON,
3233 this->statement(label);
3237 // ExpressionStat | IncDecStat | Assignment | SimpleVarDecl .
3239 // In order to make this work for if and switch statements, if
3240 // RETURN_EXP is true, and we see an ExpressionStat, we return the
3241 // expression rather than adding an expression statement to the
3242 // current block. If we see something other than an ExpressionStat,
3243 // we add the statement and return NULL.
3245 // If P_RANGE_CLAUSE is not NULL, then this will recognize a
3248 // If P_TYPE_SWITCH is not NULL, this will recognize a type switch
3249 // guard (var := expr.("type") using the literal keyword "type").
3252 Parse::simple_stat(bool may_be_composite_lit, bool return_exp,
3253 Range_clause* p_range_clause, Type_switch* p_type_switch)
3255 const Token* token = this->peek_token();
3257 // An identifier follow by := is a SimpleVarDecl.
3258 if (token->is_identifier())
3260 std::string identifier = token->identifier();
3261 bool is_exported = token->is_identifier_exported();
3262 source_location location = token->location();
3264 token = this->advance_token();
3265 if (token->is_op(OPERATOR_COLONEQ)
3266 || token->is_op(OPERATOR_COMMA))
3268 identifier = this->gogo_->pack_hidden_name(identifier, is_exported);
3269 this->simple_var_decl_or_assignment(identifier, location,
3271 (token->is_op(OPERATOR_COLONEQ)
3277 this->unget_token(Token::make_identifier_token(identifier, is_exported,
3281 Expression* exp = this->expression(PRECEDENCE_NORMAL, true,
3282 may_be_composite_lit,
3283 (p_type_switch == NULL
3285 : &p_type_switch->found));
3286 if (p_type_switch != NULL && p_type_switch->found)
3288 p_type_switch->name.clear();
3289 p_type_switch->location = exp->location();
3290 p_type_switch->expr = this->verify_not_sink(exp);
3293 token = this->peek_token();
3294 if (token->is_op(OPERATOR_PLUSPLUS) || token->is_op(OPERATOR_MINUSMINUS))
3295 this->inc_dec_stat(this->verify_not_sink(exp));
3296 else if (token->is_op(OPERATOR_COMMA)
3297 || token->is_op(OPERATOR_EQ))
3298 this->assignment(exp, p_range_clause);
3299 else if (token->is_op(OPERATOR_PLUSEQ)
3300 || token->is_op(OPERATOR_MINUSEQ)
3301 || token->is_op(OPERATOR_OREQ)
3302 || token->is_op(OPERATOR_XOREQ)
3303 || token->is_op(OPERATOR_MULTEQ)
3304 || token->is_op(OPERATOR_DIVEQ)
3305 || token->is_op(OPERATOR_MODEQ)
3306 || token->is_op(OPERATOR_LSHIFTEQ)
3307 || token->is_op(OPERATOR_RSHIFTEQ)
3308 || token->is_op(OPERATOR_ANDEQ)
3309 || token->is_op(OPERATOR_BITCLEAREQ))
3310 this->assignment(this->verify_not_sink(exp), p_range_clause);
3311 else if (return_exp)
3312 return this->verify_not_sink(exp);
3314 this->expression_stat(this->verify_not_sink(exp));
3320 Parse::simple_stat_may_start_here()
3322 return this->expression_may_start_here();
3325 // Parse { Statement ";" } which is used in a few places. The list of
3326 // statements may end with a right curly brace, in which case the
3327 // semicolon may be omitted.
3330 Parse::statement_list()
3332 while (this->statement_may_start_here())
3334 this->statement(NULL);
3335 if (this->peek_token()->is_op(OPERATOR_SEMICOLON))
3336 this->advance_token();
3337 else if (this->peek_token()->is_op(OPERATOR_RCURLY))
3341 if (!this->peek_token()->is_eof() || !saw_errors())
3342 error_at(this->location(), "expected %<;%> or %<}%> or newline");
3343 if (!this->skip_past_error(OPERATOR_RCURLY))
3350 Parse::statement_list_may_start_here()
3352 return this->statement_may_start_here();
3355 // ExpressionStat = Expression .
3358 Parse::expression_stat(Expression* exp)
3360 exp->discarding_value();
3361 this->gogo_->add_statement(Statement::make_statement(exp));
3364 // IncDecStat = Expression ( "++" | "--" ) .
3367 Parse::inc_dec_stat(Expression* exp)
3369 const Token* token = this->peek_token();
3371 // Lvalue maps require special handling.
3372 if (exp->index_expression() != NULL)
3373 exp->index_expression()->set_is_lvalue();
3375 if (token->is_op(OPERATOR_PLUSPLUS))
3376 this->gogo_->add_statement(Statement::make_inc_statement(exp));
3377 else if (token->is_op(OPERATOR_MINUSMINUS))
3378 this->gogo_->add_statement(Statement::make_dec_statement(exp));
3381 this->advance_token();
3384 // Assignment = ExpressionList assign_op ExpressionList .
3386 // EXP is an expression that we have already parsed.
3388 // If RANGE_CLAUSE is not NULL, then this will recognize a
3392 Parse::assignment(Expression* expr, Range_clause* p_range_clause)
3394 Expression_list* vars;
3395 if (!this->peek_token()->is_op(OPERATOR_COMMA))
3397 vars = new Expression_list();
3398 vars->push_back(expr);
3402 this->advance_token();
3403 vars = this->expression_list(expr, true);
3406 this->tuple_assignment(vars, p_range_clause);
3409 // An assignment statement. LHS is the list of expressions which
3410 // appear on the left hand side.
3412 // If RANGE_CLAUSE is not NULL, then this will recognize a
3416 Parse::tuple_assignment(Expression_list* lhs, Range_clause* p_range_clause)
3418 const Token* token = this->peek_token();
3419 if (!token->is_op(OPERATOR_EQ)
3420 && !token->is_op(OPERATOR_PLUSEQ)
3421 && !token->is_op(OPERATOR_MINUSEQ)
3422 && !token->is_op(OPERATOR_OREQ)
3423 && !token->is_op(OPERATOR_XOREQ)
3424 && !token->is_op(OPERATOR_MULTEQ)
3425 && !token->is_op(OPERATOR_DIVEQ)
3426 && !token->is_op(OPERATOR_MODEQ)
3427 && !token->is_op(OPERATOR_LSHIFTEQ)
3428 && !token->is_op(OPERATOR_RSHIFTEQ)
3429 && !token->is_op(OPERATOR_ANDEQ)
3430 && !token->is_op(OPERATOR_BITCLEAREQ))
3432 error_at(this->location(), "expected assignment operator");
3435 Operator op = token->op();
3436 source_location location = token->location();
3438 token = this->advance_token();
3440 if (p_range_clause != NULL && token->is_keyword(KEYWORD_RANGE))
3442 if (op != OPERATOR_EQ)
3443 error_at(this->location(), "range clause requires %<=%>");
3444 this->range_clause_expr(lhs, p_range_clause);
3448 Expression_list* vals = this->expression_list(NULL, false);
3450 // We've parsed everything; check for errors.
3451 if (lhs == NULL || vals == NULL)
3453 for (Expression_list::const_iterator pe = lhs->begin();
3457 if ((*pe)->is_error_expression())
3459 if (op != OPERATOR_EQ && (*pe)->is_sink_expression())
3460 error_at((*pe)->location(), "cannot use _ as value");
3462 for (Expression_list::const_iterator pe = vals->begin();
3466 if ((*pe)->is_error_expression())
3470 // Map expressions act differently when they are lvalues.
3471 for (Expression_list::iterator plv = lhs->begin();
3474 if ((*plv)->index_expression() != NULL)
3475 (*plv)->index_expression()->set_is_lvalue();
3477 Call_expression* call;
3478 Index_expression* map_index;
3479 Receive_expression* receive;
3480 Type_guard_expression* type_guard;
3481 if (lhs->size() == vals->size())
3484 if (lhs->size() > 1)
3486 if (op != OPERATOR_EQ)
3487 error_at(location, "multiple values only permitted with %<=%>");
3488 s = Statement::make_tuple_assignment(lhs, vals, location);
3492 if (op == OPERATOR_EQ)
3493 s = Statement::make_assignment(lhs->front(), vals->front(),
3496 s = Statement::make_assignment_operation(op, lhs->front(),
3497 vals->front(), location);
3501 this->gogo_->add_statement(s);
3503 else if (vals->size() == 1
3504 && (call = (*vals->begin())->call_expression()) != NULL)
3506 if (op != OPERATOR_EQ)
3507 error_at(location, "multiple results only permitted with %<=%>");
3509 vals = new Expression_list;
3510 for (unsigned int i = 0; i < lhs->size(); ++i)
3511 vals->push_back(Expression::make_call_result(call, i));
3512 Statement* s = Statement::make_tuple_assignment(lhs, vals, location);
3513 this->gogo_->add_statement(s);
3515 else if (lhs->size() == 2
3516 && vals->size() == 1
3517 && (map_index = (*vals->begin())->index_expression()) != NULL)
3519 if (op != OPERATOR_EQ)
3520 error_at(location, "two values from map requires %<=%>");
3521 Expression* val = lhs->front();
3522 Expression* present = lhs->back();
3523 Statement* s = Statement::make_tuple_map_assignment(val, present,
3524 map_index, location);
3525 this->gogo_->add_statement(s);
3527 else if (lhs->size() == 1
3528 && vals->size() == 2
3529 && (map_index = lhs->front()->index_expression()) != NULL)
3531 if (op != OPERATOR_EQ)
3532 error_at(location, "assigning tuple to map index requires %<=%>");
3533 Expression* val = vals->front();
3534 Expression* should_set = vals->back();
3535 Statement* s = Statement::make_map_assignment(map_index, val, should_set,
3537 this->gogo_->add_statement(s);
3539 else if (lhs->size() == 2
3540 && vals->size() == 1
3541 && (receive = (*vals->begin())->receive_expression()) != NULL)
3543 if (op != OPERATOR_EQ)
3544 error_at(location, "two values from receive requires %<=%>");
3545 Expression* val = lhs->front();
3546 Expression* success = lhs->back();
3547 Expression* channel = receive->channel();
3548 Statement* s = Statement::make_tuple_receive_assignment(val, success,
3551 this->gogo_->add_statement(s);
3553 else if (lhs->size() == 2
3554 && vals->size() == 1
3555 && (type_guard = (*vals->begin())->type_guard_expression()) != NULL)
3557 if (op != OPERATOR_EQ)
3558 error_at(location, "two values from type guard requires %<=%>");
3559 Expression* val = lhs->front();
3560 Expression* ok = lhs->back();
3561 Expression* expr = type_guard->expr();
3562 Type* type = type_guard->type();
3563 Statement* s = Statement::make_tuple_type_guard_assignment(val, ok,
3566 this->gogo_->add_statement(s);
3570 error_at(location, "number of variables does not match number of values");
3574 // GoStat = "go" Expression .
3575 // DeferStat = "defer" Expression .
3578 Parse::go_or_defer_stat()
3580 gcc_assert(this->peek_token()->is_keyword(KEYWORD_GO)
3581 || this->peek_token()->is_keyword(KEYWORD_DEFER));
3582 bool is_go = this->peek_token()->is_keyword(KEYWORD_GO);
3583 source_location stat_location = this->location();
3584 this->advance_token();
3585 source_location expr_location = this->location();
3586 Expression* expr = this->expression(PRECEDENCE_NORMAL, false, true, NULL);
3587 Call_expression* call_expr = expr->call_expression();
3588 if (call_expr == NULL)
3590 error_at(expr_location, "expected call expression");
3594 // Make it easier to simplify go/defer statements by putting every
3595 // statement in its own block.
3596 this->gogo_->start_block(stat_location);
3599 stat = Statement::make_go_statement(call_expr, stat_location);
3601 stat = Statement::make_defer_statement(call_expr, stat_location);
3602 this->gogo_->add_statement(stat);
3603 this->gogo_->add_block(this->gogo_->finish_block(stat_location),
3607 // ReturnStat = "return" [ ExpressionList ] .
3610 Parse::return_stat()
3612 gcc_assert(this->peek_token()->is_keyword(KEYWORD_RETURN));
3613 source_location location = this->location();
3614 this->advance_token();
3615 Expression_list* vals = NULL;
3616 if (this->expression_may_start_here())
3617 vals = this->expression_list(NULL, false);
3618 const Function* function = this->gogo_->current_function()->func_value();
3619 const Typed_identifier_list* results = function->type()->results();
3620 this->gogo_->add_statement(Statement::make_return_statement(results, vals,
3624 // IfStat = "if" [ [ SimpleStat ] ";" ] [ Condition ]
3625 // Block [ "else" Statement ] .
3630 gcc_assert(this->peek_token()->is_keyword(KEYWORD_IF));
3631 source_location location = this->location();
3632 this->advance_token();
3634 this->gogo_->start_block(location);
3636 Expression* cond = NULL;
3637 if (this->simple_stat_may_start_here())
3638 cond = this->simple_stat(false, true, NULL, NULL);
3639 if (cond != NULL && this->peek_token()->is_op(OPERATOR_SEMICOLON))
3641 // The SimpleStat is an expression statement.
3642 this->expression_stat(cond);
3647 if (this->peek_token()->is_op(OPERATOR_SEMICOLON))
3648 this->advance_token();
3649 if (!this->peek_token()->is_op(OPERATOR_LCURLY))
3650 cond = this->expression(PRECEDENCE_NORMAL, false, false, NULL);
3653 this->gogo_->start_block(this->location());
3654 source_location end_loc = this->block();
3655 Block* then_block = this->gogo_->finish_block(end_loc);
3657 // Check for the easy error of a newline before "else".
3658 if (this->peek_token()->is_op(OPERATOR_SEMICOLON))
3660 source_location semi_loc = this->location();
3661 if (this->advance_token()->is_keyword(KEYWORD_ELSE))
3662 error_at(this->location(),
3663 "unexpected semicolon or newline before %<else%>");
3665 this->unget_token(Token::make_operator_token(OPERATOR_SEMICOLON,
3669 Block* else_block = NULL;
3670 if (this->peek_token()->is_keyword(KEYWORD_ELSE))
3672 this->advance_token();
3673 // We create a block to gather the statement.
3674 this->gogo_->start_block(this->location());
3675 this->statement(NULL);
3676 else_block = this->gogo_->finish_block(this->location());
3679 this->gogo_->add_statement(Statement::make_if_statement(cond, then_block,
3683 this->gogo_->add_block(this->gogo_->finish_block(this->location()),
3687 // SwitchStmt = ExprSwitchStmt | TypeSwitchStmt .
3688 // ExprSwitchStmt = "switch" [ [ SimpleStat ] ";" ] [ Expression ]
3689 // "{" { ExprCaseClause } "}" .
3690 // TypeSwitchStmt = "switch" [ [ SimpleStat ] ";" ] TypeSwitchGuard
3691 // "{" { TypeCaseClause } "}" .
3692 // TypeSwitchGuard = [ identifier ":=" ] Expression "." "(" "type" ")" .
3695 Parse::switch_stat(const Label* label)
3697 gcc_assert(this->peek_token()->is_keyword(KEYWORD_SWITCH));
3698 source_location location = this->location();
3699 this->advance_token();
3701 this->gogo_->start_block(location);
3703 Expression* switch_val = NULL;
3704 Type_switch type_switch;
3705 if (this->simple_stat_may_start_here())
3706 switch_val = this->simple_stat(false, true, NULL, &type_switch);
3707 if (switch_val != NULL && this->peek_token()->is_op(OPERATOR_SEMICOLON))
3709 // The SimpleStat is an expression statement.
3710 this->expression_stat(switch_val);
3713 if (switch_val == NULL && !type_switch.found)
3715 if (this->peek_token()->is_op(OPERATOR_SEMICOLON))
3716 this->advance_token();
3717 if (!this->peek_token()->is_op(OPERATOR_LCURLY))
3719 if (this->peek_token()->is_identifier())
3721 const Token* token = this->peek_token();
3722 std::string identifier = token->identifier();
3723 bool is_exported = token->is_identifier_exported();
3724 source_location id_loc = token->location();
3726 token = this->advance_token();
3727 bool is_coloneq = token->is_op(OPERATOR_COLONEQ);
3728 this->unget_token(Token::make_identifier_token(identifier,
3733 // This must be a TypeSwitchGuard.
3734 switch_val = this->simple_stat(false, true, NULL,
3736 if (!type_switch.found
3737 && !switch_val->is_error_expression())
3739 error_at(id_loc, "expected type switch assignment");
3740 switch_val = Expression::make_error(id_loc);
3744 if (switch_val == NULL && !type_switch.found)
3746 switch_val = this->expression(PRECEDENCE_NORMAL, false, false,
3747 &type_switch.found);
3748 if (type_switch.found)
3750 type_switch.name.clear();
3751 type_switch.expr = switch_val;
3752 type_switch.location = switch_val->location();
3758 if (!this->peek_token()->is_op(OPERATOR_LCURLY))
3760 source_location token_loc = this->location();
3761 if (this->peek_token()->is_op(OPERATOR_SEMICOLON)
3762 && this->advance_token()->is_op(OPERATOR_LCURLY))
3763 error_at(token_loc, "unexpected semicolon or newline before %<{%>");
3766 error_at(this->location(), "expected %<{%>");
3767 this->gogo_->add_block(this->gogo_->finish_block(this->location()),
3772 this->advance_token();
3774 Statement* statement;
3775 if (type_switch.found)
3776 statement = this->type_switch_body(label, type_switch, location);
3778 statement = this->expr_switch_body(label, switch_val, location);
3780 if (statement != NULL)
3781 this->gogo_->add_statement(statement);
3783 this->gogo_->add_block(this->gogo_->finish_block(this->location()),
3787 // The body of an expression switch.
3788 // "{" { ExprCaseClause } "}"
3791 Parse::expr_switch_body(const Label* label, Expression* switch_val,
3792 source_location location)
3794 Switch_statement* statement = Statement::make_switch_statement(switch_val,
3797 this->push_break_statement(statement, label);
3799 Case_clauses* case_clauses = new Case_clauses();
3800 while (!this->peek_token()->is_op(OPERATOR_RCURLY))
3802 if (this->peek_token()->is_eof())
3805 error_at(this->location(), "missing %<}%>");
3808 this->expr_case_clause(case_clauses);
3810 this->advance_token();
3812 statement->add_clauses(case_clauses);
3814 this->pop_break_statement();
3819 // ExprCaseClause = ExprSwitchCase ":" [ StatementList ] .
3820 // FallthroughStat = "fallthrough" .
3823 Parse::expr_case_clause(Case_clauses* clauses)
3825 source_location location = this->location();
3827 bool is_default = false;
3828 Expression_list* vals = this->expr_switch_case(&is_default);
3830 if (!this->peek_token()->is_op(OPERATOR_COLON))
3833 error_at(this->location(), "expected %<:%>");
3837 this->advance_token();
3839 Block* statements = NULL;
3840 if (this->statement_list_may_start_here())
3842 this->gogo_->start_block(this->location());
3843 this->statement_list();
3844 statements = this->gogo_->finish_block(this->location());
3847 bool is_fallthrough = false;
3848 if (this->peek_token()->is_keyword(KEYWORD_FALLTHROUGH))
3850 is_fallthrough = true;
3851 if (this->advance_token()->is_op(OPERATOR_SEMICOLON))
3852 this->advance_token();
3855 if (is_default || vals != NULL)
3856 clauses->add(vals, is_default, statements, is_fallthrough, location);
3859 // ExprSwitchCase = "case" ExpressionList | "default" .
3862 Parse::expr_switch_case(bool* is_default)
3864 const Token* token = this->peek_token();
3865 if (token->is_keyword(KEYWORD_CASE))
3867 this->advance_token();
3868 return this->expression_list(NULL, false);
3870 else if (token->is_keyword(KEYWORD_DEFAULT))
3872 this->advance_token();
3879 error_at(this->location(), "expected %<case%> or %<default%>");
3880 if (!token->is_op(OPERATOR_RCURLY))
3881 this->advance_token();
3886 // The body of a type switch.
3887 // "{" { TypeCaseClause } "}" .
3890 Parse::type_switch_body(const Label* label, const Type_switch& type_switch,
3891 source_location location)
3893 Named_object* switch_no = NULL;
3894 if (!type_switch.name.empty())
3896 Variable* switch_var = new Variable(NULL, type_switch.expr, false, false,
3897 false, type_switch.location);
3898 switch_no = this->gogo_->add_variable(type_switch.name, switch_var);
3901 Type_switch_statement* statement =
3902 Statement::make_type_switch_statement(switch_no,
3908 this->push_break_statement(statement, label);
3910 Type_case_clauses* case_clauses = new Type_case_clauses();
3911 while (!this->peek_token()->is_op(OPERATOR_RCURLY))
3913 if (this->peek_token()->is_eof())
3915 error_at(this->location(), "missing %<}%>");
3918 this->type_case_clause(switch_no, case_clauses);
3920 this->advance_token();
3922 statement->add_clauses(case_clauses);
3924 this->pop_break_statement();
3929 // TypeCaseClause = TypeSwitchCase ":" [ StatementList ] .
3932 Parse::type_case_clause(Named_object* switch_no, Type_case_clauses* clauses)
3934 source_location location = this->location();
3936 std::vector<Type*> types;
3937 bool is_default = false;
3938 this->type_switch_case(&types, &is_default);
3940 if (!this->peek_token()->is_op(OPERATOR_COLON))
3941 error_at(this->location(), "expected %<:%>");
3943 this->advance_token();
3945 Block* statements = NULL;
3946 if (this->statement_list_may_start_here())
3948 this->gogo_->start_block(this->location());
3949 if (switch_no != NULL && types.size() == 1)
3951 Type* type = types.front();
3952 Expression* init = Expression::make_var_reference(switch_no,
3954 init = Expression::make_type_guard(init, type, location);
3955 Variable* v = new Variable(type, init, false, false, false,
3957 v->set_is_type_switch_var();
3958 this->gogo_->add_variable(switch_no->name(), v);
3960 this->statement_list();
3961 statements = this->gogo_->finish_block(this->location());
3964 if (this->peek_token()->is_keyword(KEYWORD_FALLTHROUGH))
3966 error_at(this->location(),
3967 "fallthrough is not permitted in a type switch");
3968 if (this->advance_token()->is_op(OPERATOR_SEMICOLON))
3969 this->advance_token();
3974 gcc_assert(types.empty());
3975 clauses->add(NULL, false, true, statements, location);
3977 else if (!types.empty())
3979 for (std::vector<Type*>::const_iterator p = types.begin();
3980 p + 1 != types.end();
3982 clauses->add(*p, true, false, NULL, location);
3983 clauses->add(types.back(), false, false, statements, location);
3987 // TypeSwitchCase = "case" type | "default"
3989 // We accept a comma separated list of types.
3992 Parse::type_switch_case(std::vector<Type*>* types, bool* is_default)
3994 const Token* token = this->peek_token();
3995 if (token->is_keyword(KEYWORD_CASE))
3997 this->advance_token();
4000 Type* t = this->type();
4001 if (!t->is_error_type())
4002 types->push_back(t);
4003 if (!this->peek_token()->is_op(OPERATOR_COMMA))
4005 this->advance_token();
4008 else if (token->is_keyword(KEYWORD_DEFAULT))
4010 this->advance_token();
4015 error_at(this->location(), "expected %<case%> or %<default%>");
4016 if (!token->is_op(OPERATOR_RCURLY))
4017 this->advance_token();
4021 // SelectStat = "select" "{" { CommClause } "}" .
4024 Parse::select_stat(const Label* label)
4026 gcc_assert(this->peek_token()->is_keyword(KEYWORD_SELECT));
4027 source_location location = this->location();
4028 const Token* token = this->advance_token();
4030 if (!token->is_op(OPERATOR_LCURLY))
4032 source_location token_loc = token->location();
4033 if (token->is_op(OPERATOR_SEMICOLON)
4034 && this->advance_token()->is_op(OPERATOR_LCURLY))
4035 error_at(token_loc, "unexpected semicolon or newline before %<{%>");
4038 error_at(this->location(), "expected %<{%>");
4042 this->advance_token();
4044 Select_statement* statement = Statement::make_select_statement(location);
4046 this->push_break_statement(statement, label);
4048 Select_clauses* select_clauses = new Select_clauses();
4049 while (!this->peek_token()->is_op(OPERATOR_RCURLY))
4051 if (this->peek_token()->is_eof())
4053 error_at(this->location(), "expected %<}%>");
4056 this->comm_clause(select_clauses);
4059 this->advance_token();
4061 statement->add_clauses(select_clauses);
4063 this->pop_break_statement();
4065 this->gogo_->add_statement(statement);
4068 // CommClause = CommCase [ StatementList ] .
4071 Parse::comm_clause(Select_clauses* clauses)
4073 source_location location = this->location();
4074 bool is_send = false;
4075 Expression* channel = NULL;
4076 Expression* val = NULL;
4077 std::string varname;
4078 bool is_default = false;
4079 bool got_case = this->comm_case(&is_send, &channel, &val, &varname,
4082 Block* statements = NULL;
4083 Named_object* var = NULL;
4084 if (this->peek_token()->is_op(OPERATOR_SEMICOLON))
4085 this->advance_token();
4086 else if (this->statement_list_may_start_here())
4088 this->gogo_->start_block(this->location());
4090 if (!varname.empty())
4092 // FIXME: LOCATION is slightly wrong here.
4093 Variable* v = new Variable(NULL, channel, false, false, false,
4095 v->set_type_from_chan_element();
4096 var = this->gogo_->add_variable(varname, v);
4099 this->statement_list();
4100 statements = this->gogo_->finish_block(this->location());
4104 clauses->add(is_send, channel, val, var, is_default, statements, location);
4107 // CommCase = ( "default" | ( "case" ( SendExpr | RecvExpr) ) ) ":" .
4110 Parse::comm_case(bool* is_send, Expression** channel, Expression** val,
4111 std::string* varname, bool* is_default)
4113 const Token* token = this->peek_token();
4114 if (token->is_keyword(KEYWORD_DEFAULT))
4116 this->advance_token();
4119 else if (token->is_keyword(KEYWORD_CASE))
4121 this->advance_token();
4122 if (!this->send_or_recv_expr(is_send, channel, val, varname))
4127 error_at(this->location(), "expected %<case%> or %<default%>");
4128 if (!token->is_op(OPERATOR_RCURLY))
4129 this->advance_token();
4133 if (!this->peek_token()->is_op(OPERATOR_COLON))
4135 error_at(this->location(), "expected colon");
4139 this->advance_token();
4144 // SendExpr = Expression "<-" Expression .
4145 // RecvExpr = [ Expression ( "=" | ":=" ) ] "<-" Expression .
4148 Parse::send_or_recv_expr(bool* is_send, Expression** channel, Expression** val,
4149 std::string* varname)
4151 const Token* token = this->peek_token();
4152 source_location location = token->location();
4153 if (token->is_identifier())
4155 std::string recv_var = token->identifier();
4156 bool is_var_exported = token->is_identifier_exported();
4157 if (!this->advance_token()->is_op(OPERATOR_COLONEQ))
4158 this->unget_token(Token::make_identifier_token(recv_var,
4163 if (!this->advance_token()->is_op(OPERATOR_CHANOP))
4165 error_at(this->location(), "expected %<<-%>");
4169 *varname = this->gogo_->pack_hidden_name(recv_var, is_var_exported);
4170 this->advance_token();
4171 *channel = this->expression(PRECEDENCE_NORMAL, false, true, NULL);
4176 if (this->peek_token()->is_op(OPERATOR_CHANOP))
4179 this->advance_token();
4180 *channel = this->expression(PRECEDENCE_NORMAL, false, true, NULL);
4184 Expression* left = this->expression(PRECEDENCE_CHANOP, true, true, NULL);
4186 if (this->peek_token()->is_op(OPERATOR_EQ))
4188 if (!this->advance_token()->is_op(OPERATOR_CHANOP))
4190 error_at(this->location(), "missing %<<-%>");
4195 this->advance_token();
4196 *channel = this->expression(PRECEDENCE_NORMAL, false, true, NULL);
4198 else if (this->peek_token()->is_op(OPERATOR_CHANOP))
4201 *channel = this->verify_not_sink(left);
4202 this->advance_token();
4203 *val = this->expression(PRECEDENCE_NORMAL, false, true, NULL);
4207 error_at(this->location(), "expected %<<-%> or %<=%>");
4215 // ForStat = "for" [ Condition | ForClause | RangeClause ] Block .
4216 // Condition = Expression .
4219 Parse::for_stat(const Label* label)
4221 gcc_assert(this->peek_token()->is_keyword(KEYWORD_FOR));
4222 source_location location = this->location();
4223 const Token* token = this->advance_token();
4225 // Open a block to hold any variables defined in the init statement
4226 // of the for statement.
4227 this->gogo_->start_block(location);
4230 Expression* cond = NULL;
4232 Range_clause range_clause;
4234 if (!token->is_op(OPERATOR_LCURLY))
4236 if (token->is_keyword(KEYWORD_VAR))
4238 error_at(this->location(),
4239 "var declaration not allowed in for initializer");
4243 if (token->is_op(OPERATOR_SEMICOLON))
4244 this->for_clause(&cond, &post);
4247 // We might be looking at a Condition, an InitStat, or a
4249 cond = this->simple_stat(false, true, &range_clause, NULL);
4250 if (!this->peek_token()->is_op(OPERATOR_SEMICOLON))
4252 if (cond == NULL && !range_clause.found)
4253 error_at(this->location(), "parse error in for statement");
4257 if (range_clause.found)
4258 error_at(this->location(), "parse error after range clause");
4262 // COND is actually an expression statement for
4263 // InitStat at the start of a ForClause.
4264 this->expression_stat(cond);
4268 this->for_clause(&cond, &post);
4273 // Build the For_statement and note that it is the current target
4274 // for break and continue statements.
4276 For_statement* sfor;
4277 For_range_statement* srange;
4279 if (!range_clause.found)
4281 sfor = Statement::make_for_statement(init, cond, post, location);
4287 srange = Statement::make_for_range_statement(range_clause.index,
4295 this->push_break_statement(s, label);
4296 this->push_continue_statement(s, label);
4298 // Gather the block of statements in the loop and add them to the
4301 this->gogo_->start_block(this->location());
4302 source_location end_loc = this->block();
4303 Block* statements = this->gogo_->finish_block(end_loc);
4306 sfor->add_statements(statements);
4308 srange->add_statements(statements);
4310 // This is no longer the break/continue target.
4311 this->pop_break_statement();
4312 this->pop_continue_statement();
4314 // Add the For_statement to the list of statements, and close out
4315 // the block we started to hold any variables defined in the for
4318 this->gogo_->add_statement(s);
4320 this->gogo_->add_block(this->gogo_->finish_block(this->location()),
4324 // ForClause = [ InitStat ] ";" [ Condition ] ";" [ PostStat ] .
4325 // InitStat = SimpleStat .
4326 // PostStat = SimpleStat .
4328 // We have already read InitStat at this point.
4331 Parse::for_clause(Expression** cond, Block** post)
4333 gcc_assert(this->peek_token()->is_op(OPERATOR_SEMICOLON));
4334 this->advance_token();
4335 if (this->peek_token()->is_op(OPERATOR_SEMICOLON))
4337 else if (this->peek_token()->is_op(OPERATOR_LCURLY))
4339 error_at(this->location(),
4340 "unexpected semicolon or newline before %<{%>");
4346 *cond = this->expression(PRECEDENCE_NORMAL, false, true, NULL);
4347 if (!this->peek_token()->is_op(OPERATOR_SEMICOLON))
4348 error_at(this->location(), "expected semicolon");
4350 this->advance_token();
4352 if (this->peek_token()->is_op(OPERATOR_LCURLY))
4356 this->gogo_->start_block(this->location());
4357 this->simple_stat(false, false, NULL, NULL);
4358 *post = this->gogo_->finish_block(this->location());
4362 // RangeClause = IdentifierList ( "=" | ":=" ) "range" Expression .
4364 // This is the := version. It is called with a list of identifiers.
4367 Parse::range_clause_decl(const Typed_identifier_list* til,
4368 Range_clause* p_range_clause)
4370 gcc_assert(this->peek_token()->is_keyword(KEYWORD_RANGE));
4371 source_location location = this->location();
4373 p_range_clause->found = true;
4375 gcc_assert(til->size() >= 1);
4376 if (til->size() > 2)
4377 error_at(this->location(), "too many variables for range clause");
4379 this->advance_token();
4380 Expression* expr = this->expression(PRECEDENCE_NORMAL, false, false, NULL);
4381 p_range_clause->range = expr;
4383 bool any_new = false;
4385 const Typed_identifier* pti = &til->front();
4386 Named_object* no = this->init_var(*pti, NULL, expr, true, true, &any_new);
4387 if (any_new && no->is_variable())
4388 no->var_value()->set_type_from_range_index();
4389 p_range_clause->index = Expression::make_var_reference(no, location);
4391 if (til->size() == 1)
4392 p_range_clause->value = NULL;
4396 bool is_new = false;
4397 no = this->init_var(*pti, NULL, expr, true, true, &is_new);
4398 if (is_new && no->is_variable())
4399 no->var_value()->set_type_from_range_value();
4402 p_range_clause->value = Expression::make_var_reference(no, location);
4406 error_at(location, "variables redeclared but no variable is new");
4409 // The = version of RangeClause. This is called with a list of
4413 Parse::range_clause_expr(const Expression_list* vals,
4414 Range_clause* p_range_clause)
4416 gcc_assert(this->peek_token()->is_keyword(KEYWORD_RANGE));
4418 p_range_clause->found = true;
4420 gcc_assert(vals->size() >= 1);
4421 if (vals->size() > 2)
4422 error_at(this->location(), "too many variables for range clause");
4424 this->advance_token();
4425 p_range_clause->range = this->expression(PRECEDENCE_NORMAL, false, false,
4428 p_range_clause->index = vals->front();
4429 if (vals->size() == 1)
4430 p_range_clause->value = NULL;
4432 p_range_clause->value = vals->back();
4435 // Push a statement on the break stack.
4438 Parse::push_break_statement(Statement* enclosing, const Label* label)
4440 this->break_stack_.push_back(std::make_pair(enclosing, label));
4443 // Push a statement on the continue stack.
4446 Parse::push_continue_statement(Statement* enclosing, const Label* label)
4448 this->continue_stack_.push_back(std::make_pair(enclosing, label));
4451 // Pop the break stack.
4454 Parse::pop_break_statement()
4456 this->break_stack_.pop_back();
4459 // Pop the continue stack.
4462 Parse::pop_continue_statement()
4464 this->continue_stack_.pop_back();
4467 // Find a break or continue statement given a label name.
4470 Parse::find_bc_statement(const Bc_stack* bc_stack, const std::string& label)
4472 for (Bc_stack::const_reverse_iterator p = bc_stack->rbegin();
4473 p != bc_stack->rend();
4475 if (p->second != NULL && p->second->name() == label)
4480 // BreakStat = "break" [ identifier ] .
4485 gcc_assert(this->peek_token()->is_keyword(KEYWORD_BREAK));
4486 source_location location = this->location();
4488 const Token* token = this->advance_token();
4489 Statement* enclosing;
4490 if (!token->is_identifier())
4492 if (this->break_stack_.empty())
4494 error_at(this->location(),
4495 "break statement not within for or switch or select");
4498 enclosing = this->break_stack_.back().first;
4502 enclosing = this->find_bc_statement(&this->break_stack_,
4503 token->identifier());
4504 if (enclosing == NULL)
4506 error_at(token->location(),
4507 ("break label %qs not associated with "
4508 "for or switch or select"),
4509 Gogo::message_name(token->identifier()).c_str());
4510 this->advance_token();
4513 this->advance_token();
4516 Unnamed_label* label;
4517 if (enclosing->classification() == Statement::STATEMENT_FOR)
4518 label = enclosing->for_statement()->break_label();
4519 else if (enclosing->classification() == Statement::STATEMENT_FOR_RANGE)
4520 label = enclosing->for_range_statement()->break_label();
4521 else if (enclosing->classification() == Statement::STATEMENT_SWITCH)
4522 label = enclosing->switch_statement()->break_label();
4523 else if (enclosing->classification() == Statement::STATEMENT_TYPE_SWITCH)
4524 label = enclosing->type_switch_statement()->break_label();
4525 else if (enclosing->classification() == Statement::STATEMENT_SELECT)
4526 label = enclosing->select_statement()->break_label();
4530 this->gogo_->add_statement(Statement::make_break_statement(label,
4534 // ContinueStat = "continue" [ identifier ] .
4537 Parse::continue_stat()
4539 gcc_assert(this->peek_token()->is_keyword(KEYWORD_CONTINUE));
4540 source_location location = this->location();
4542 const Token* token = this->advance_token();
4543 Statement* enclosing;
4544 if (!token->is_identifier())
4546 if (this->continue_stack_.empty())
4548 error_at(this->location(), "continue statement not within for");
4551 enclosing = this->continue_stack_.back().first;
4555 enclosing = this->find_bc_statement(&this->continue_stack_,
4556 token->identifier());
4557 if (enclosing == NULL)
4559 error_at(token->location(),
4560 "continue label %qs not associated with for",
4561 Gogo::message_name(token->identifier()).c_str());
4562 this->advance_token();
4565 this->advance_token();
4568 Unnamed_label* label;
4569 if (enclosing->classification() == Statement::STATEMENT_FOR)
4570 label = enclosing->for_statement()->continue_label();
4571 else if (enclosing->classification() == Statement::STATEMENT_FOR_RANGE)
4572 label = enclosing->for_range_statement()->continue_label();
4576 this->gogo_->add_statement(Statement::make_continue_statement(label,
4580 // GotoStat = "goto" identifier .
4585 gcc_assert(this->peek_token()->is_keyword(KEYWORD_GOTO));
4586 source_location location = this->location();
4587 const Token* token = this->advance_token();
4588 if (!token->is_identifier())
4589 error_at(this->location(), "expected label for goto");
4592 Label* label = this->gogo_->add_label_reference(token->identifier());
4593 Statement* s = Statement::make_goto_statement(label, location);
4594 this->gogo_->add_statement(s);
4595 this->advance_token();
4599 // PackageClause = "package" PackageName .
4602 Parse::package_clause()
4604 const Token* token = this->peek_token();
4605 source_location location = token->location();
4607 if (!token->is_keyword(KEYWORD_PACKAGE))
4609 error_at(this->location(), "program must start with package clause");
4614 token = this->advance_token();
4615 if (token->is_identifier())
4617 name = token->identifier();
4620 error_at(this->location(), "invalid package name _");
4623 this->advance_token();
4627 error_at(this->location(), "package name must be an identifier");
4631 this->gogo_->set_package_name(name, location);
4634 // ImportDecl = "import" Decl<ImportSpec> .
4637 Parse::import_decl()
4639 gcc_assert(this->peek_token()->is_keyword(KEYWORD_IMPORT));
4640 this->advance_token();
4641 this->decl(&Parse::import_spec, NULL);
4644 // ImportSpec = [ "." | PackageName ] PackageFileName .
4647 Parse::import_spec(void*)
4649 const Token* token = this->peek_token();
4650 source_location location = token->location();
4652 std::string local_name;
4653 bool is_local_name_exported = false;
4654 if (token->is_op(OPERATOR_DOT))
4657 token = this->advance_token();
4659 else if (token->is_identifier())
4661 local_name = token->identifier();
4662 is_local_name_exported = token->is_identifier_exported();
4663 token = this->advance_token();
4666 if (!token->is_string())
4668 error_at(this->location(), "missing import package name");
4672 this->gogo_->import_package(token->string_value(), local_name,
4673 is_local_name_exported, location);
4675 this->advance_token();
4678 // SourceFile = PackageClause ";" { ImportDecl ";" }
4679 // { TopLevelDecl ";" } .
4684 this->package_clause();
4686 const Token* token = this->peek_token();
4687 if (token->is_op(OPERATOR_SEMICOLON))
4688 token = this->advance_token();
4690 error_at(this->location(),
4691 "expected %<;%> or newline after package clause");
4693 while (token->is_keyword(KEYWORD_IMPORT))
4695 this->import_decl();
4696 token = this->peek_token();
4697 if (token->is_op(OPERATOR_SEMICOLON))
4698 token = this->advance_token();
4700 error_at(this->location(),
4701 "expected %<;%> or newline after import declaration");
4704 while (!token->is_eof())
4706 if (this->declaration_may_start_here())
4707 this->declaration();
4710 error_at(this->location(), "expected declaration");
4712 this->advance_token();
4713 while (!this->peek_token()->is_eof()
4714 && !this->peek_token()->is_op(OPERATOR_SEMICOLON)
4715 && !this->peek_token()->is_op(OPERATOR_RCURLY));
4716 if (!this->peek_token()->is_eof()
4717 && !this->peek_token()->is_op(OPERATOR_SEMICOLON))
4718 this->advance_token();
4720 token = this->peek_token();
4721 if (token->is_op(OPERATOR_SEMICOLON))
4722 token = this->advance_token();
4723 else if (!token->is_eof() || !saw_errors())
4725 error_at(this->location(),
4726 "expected %<;%> or newline after top level declaration");
4727 this->skip_past_error(OPERATOR_INVALID);
4732 // Reset the current iota value.
4740 // Return the current iota value.
4748 // Increment the current iota value.
4751 Parse::increment_iota()
4756 // Skip forward to a semicolon or OP. OP will normally be
4757 // OPERATOR_RPAREN or OPERATOR_RCURLY. If we find a semicolon, move
4758 // past it and return. If we find OP, it will be the next token to
4759 // read. Return true if we are OK, false if we found EOF.
4762 Parse::skip_past_error(Operator op)
4764 const Token* token = this->peek_token();
4765 while (!token->is_op(op))
4767 if (token->is_eof())
4769 if (token->is_op(OPERATOR_SEMICOLON))
4771 this->advance_token();
4774 token = this->advance_token();
4779 // Check that an expression is not a sink.
4782 Parse::verify_not_sink(Expression* expr)
4784 if (expr->is_sink_expression())
4786 error_at(expr->location(), "cannot use _ as value");
4787 expr = Expression::make_error(expr->location());