@ifset INTERNALS
@ifset USING
This file documents the use and the internals of the GNU Treelang
-(@code{treelang}) compiler. At the moment this manual is not
-incorporated into the main GCC manual as it is too incomplete. It
+(@code{treelang}) compiler. At the moment this manual is not
+incorporated into the main GCC manual as it is incomplete. It
corresponds to the @value{which-treelang} version of @code{treelang}.
@end ifset
@end ifset
@insertcopying
@end ifnottex
-treelang was Contributed by Tim Josling (@email{@value{email-josling}}).
-Inspired by and based on the 'toy' language, written by Richard Kenner.
-
-This document was written by Tim Josling, based on the GNU C++
-documentation.
-
@setchapternewpage odd
@c @finalout
@titlepage
@ifset INTERNALS
@ifset USING
-This manual documents how to run, install and maintain @code{treelang},
-as well as its new features and incompatibilities,
-and how to report bugs.
-It corresponds to the @value{which-treelang} version of @code{treelang}.
+This manual documents how to run, install and maintain @code{treelang}.
+It also documents the features and incompatibilities in the @value{which-treelang}
+version of @code{treelang}.
@end ifset
@end ifset
@ifclear INTERNALS
-This manual documents how to run and install @code{treelang},
-as well as its new features and incompatibilities, and how to report
-bugs.
-It corresponds to the @value{which-treelang} version of @code{treelang}.
+This manual documents how to run and install @code{treelang}.
+It also documents the features and incompatibilities in the @value{which-treelang}
+version of @code{treelang}.
@end ifclear
@ifclear USING
-This manual documents how to maintain @code{treelang}, as well as its
-new features and incompatibilities, and how to report bugs. It
-corresponds to the @value{which-treelang} version of @code{treelang}.
+This manual documents how to maintain @code{treelang}.
+It also documents the features and incompatibilities in the @value{which-treelang}
+version of @code{treelang}.
@end ifclear
@end ifnottex
@item ;
used to end a statement
@item +
-addition
+addition, or unary plus for signed literals
@item -
-subtraction
+subtraction, or unary minus for signed literals
@item =
assignment
@item ==
@item static
indicate variable is permanent, or function has file scope only
@item automatic
-indicate that variable is allocated for the life of the function
+indicate that variable is allocated for the life of the current scope
@item external_reference
indicate that variable or function is defined in another file
@item external_definition
@enumerate 1
@item
-automatic: This means a variable is allocated at start of function and
-released when the function returns. This can only be used for variables
-within functions. It cannot be used for functions.
+automatic: This means a variable is allocated at start of the current scope and
+released when the current scope is exited. This can only be used for variables
+within functions. It cannot be used for functions.
@item
static: This means a variable is allocated at start of program and
@item
parameter: variable_declaration ,
-The variable declarations must not have initialisations.
+The variable declarations must not have initializations.
@item
initial: = value
@item
value: integer_constant
+Values without a unary plus or minus are considered to be unsigned.
@smallexample
-eg 1 +2 -3
+e.g.@: 1 +2 -3
@end smallexample
@item
-function_declaration: name @{variable_declarations statements @}
+function_declaration: name @{ variable_declarations statements @}
A function consists of the function name then the declarations (if any)
and statements (if any) within one pair of braces.
The details of the function arguments come from the function
-prototype. The function prototype must precede the function declaration
+prototype. The function prototype must precede the function declaration
in the file.
@item
statement: if_statement OR expression_statement OR return_statement
@item
-if_statement: if (expression) @{ statements @} else @{ statements @}
+if_statement: if ( expression ) @{ variable_declarations statements @}
+else @{ variable_declarations statements @}
The first lot of statements is executed if the expression is
-nonzero. Otherwise the second lot of statements is executed. Either
+nonzero. Otherwise the second lot of statements is executed. Either
list of statements may be empty, but both sets of braces and the else must be present.
@smallexample
@item
expression_statement: expression;
-The expression is executed and any side effects, such
+The expression is executed, including any side effects.
@item
return_statement: return expression_opt;
@cindex warnings
@cindex questionable instructions
@item
-There are no warnings in treelang. A program is either correct or in
-error.
+There are few warnings in treelang. A program is either correct or in
+error. The only exception to this is an expression in a return statement for
+functions that return nothing.
@end itemize
@cindex components of treelang
(and C++) code, with one proviso.
C promotes small integer types to 'int' when used as function parameters and
-return values. The treelang compiler does not do this, so if you want to interface
-to C, you need to specify the promoted value, not the nominal value.
+return values in non-prototyped functions. Since treelang has no
+non-prototyped functions, the treelang compiler does not do this.
@ifset INTERNALS
@node treelang internals, Open Questions, Other Languages, Top
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