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Last modified Dec 17, 2003.

Pragmas

	Pragma:
	    pragma ( Identifier )
	    pragma ( Identifier , ExpressionList )
	
Pragmas are a way to pass special information to the compiler and to add vendor specific extensions to D. Pragmas can be used by themselves terminated with a ';', they can influence a statement, a block of statements, a declaration, or a block of declarations.
	pragma(ident);		// just by itself

	pragma(ident) declaration; // influence one declaration

	pragma(ident):		// influence subsequent declarations
		declaration;
		declaration;

	pragma(ident)		// influence block of declarations
	{	declaration;
		declaration;
	}

	pragma(ident) statement; // influence one statement

	pragma(ident)		// influence block of statements
	{	statement;
		statement;
	}
	
The kind of pragma it is is determined by the Identifier. ExpressionList is a comma-separated list of AssignExpressions. The AssignExpressions must be parsable as expressions, but what they mean semantically is up to the individual pragma semantics.

Predefined Pragmas

All implementations must support these, even if by just ignoring them:
msg
Prints a message while compiling, the AssignExpressions must be string literals:
	pragma(msg, "compiling...");
    

Vendor Specific Pragmas

Vendor specific pragma Identifiers can be defined if they are prefixed by the vendor's trademarked name, in a similar manner to version identifiers:
	pragma(DigitalMars_funky_extension) { ... }
	
Compilers must diagnose an error for unrecognized Pragmas, even if they are vendor specific ones. This implies that vendor specific pragmas should be wrapped in version statements:
	version (DigitalMars)
	{
	    pragma(DigitalMars_funky_extension) { ... }
	}
	

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