Preprocessor BLocks

This defines some macros that can be used to ensure that certain operations are always executed before entering and after leaving a particular block. More...

Collaboration diagram for Preprocessor BLocks:

Modules
	Checking code validity
	Try, catch and finally blocks
Defines
#define	P99_AVOID   for (;0;)
	Only execute the depending statement or block if it is jumped into explicitly from the outer block.
#define	P99_BLOCK(...)   P99_PREFER(__VA_ARGS__) P99_NOP
	Execute the statements in the argument list.
#define	P99_BLOCK_DOCUMENT
	Add some default documentation and links to the following block macro.
#define	P99_GUARDED_BLOCK(T, NAME, INITIAL, BEFORE, AFTER)
	A meta-macro to protect a dependent block or statement by a guard variable NAME of type T.
#define	P99_HANDLE_ERRNO
	Handle and reset errno.
#define	P99_INVARIANT(EXPR)   P99_PROTECTED_BLOCK(assert((EXPR) && "failed on entry"), assert((EXPR) && "failed on leave"))
	Assert runtime condition EXPR on entry and on leave of the dependent block.
#define	P99_NOP   ((void)0)
	Do nothing.
#define	P99_PREFER(...)   if (1) { __VA_ARGS__ } else
	Prefer the statements in the argument list over the statement or block that follows.
#define	P99_PROTECT
	The pseudo label to which we jump when we unwind the stack with P99_UNWIND.
#define	P99_PROTECTED_BLOCK(BEFORE, AFTER)
	A meta-macro to protect a dependent block or statement by statement BEFORE that is executed before the block and AFTER that is executed afterward.
#define	P99_UNCASE   P00_UNCASE :
	A command prefixed with this cannot be a case target from surrounding scopes.
#define	P99_UNWIND(X)   p00_unwind(p00_unwind_top, p99_unwind_level, (X))
	Preliminary resume from one or several levels of nested P99_UNWIND_PROTECT.
#define	P99_UNWIND_PROTECT
	Unwind execution from several levels of nesting inside a function.
#define	P99_UNWIND_RETURN
	Return from the enclosing function after unwinding all levels of nested P99_UNWIND_PROTECT.
#define	P99_XCASE   P99_AVOID case
	An exclusive case for a switch statement.
#define	P99_XDEFAULT   P99_AVOID default
	The default case analogous to P99_XCASE.
Enumerations
enum	p99_unwind { p99_unwind_level = 0 , p99_unwind_code = 0, p99_unwind_return = INT_MAX }

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Detailed Description

This defines some macros that can be used to ensure that certain operations are always executed before entering and after leaving a particular block.