for P99_BLK_MARK P99_BLOCK_DOCUMENT P99_CASERANGE P99_DO P99_FORALL P99_GUARDED_BLOCK P99_HANDLE_ERRNO P99_INVARIANT P99_MARK P99_NOP P99_PARALLEL_DO P99_PARALLEL_FOR P99_PARALLEL_FORALL P99_PROTECT P99_PROTECTED_BLOCK P99_SIMPLE_BLOCKS P99_UNCASE p99_unwind P99_UNWIND p99_unwind_code P99_UNWIND_PROTECT P99_UNWIND_RETURN

P99_PROTECTED_BLOCK #define P99_PROTECTED_BLOCK (   BEFORE,   AFTER  ) A meta-macro to protect a dependent block or statement by the statements BEFORE that is executed before the block and AFTER that is executed afterward. Early exit from the block is possible with break or continue. Warning return, exit() or other functions that don't return to the caller inside the dependent block will result in not executing AFTER, so be careful. An example of a potential use is #define P99_INVARIANT(EXPR) P99_PROTECTED_BLOCK(assert((EXPR) && "failed on entry"), assert((EXPR) && "failed on leave")) Such a construct may then be used like this P99_INVARIANT(x > 5) { // do something with x that changes it but ensures that // it will be strictly less than 5 at the end } and this would trigger an assertion whenever the condition is not fulfilled when entering or leaving the block. Definition at line 217 of file p99_block.h.