AX_C_DECLARE_BLOCK
The macro will compile a test program to see whether the compiler does allow new variable declarations in the middle of a C statement block, i.e. after some non-declaration line. New compilers will allow that which makes the behave a bit more like C++ - the gcc did support it for quite a time already.
#define DECLARE_BLOCK_NEEDED says they need to be at the beginning of of a statement block. Additionally two defines DECLARE_BLOCK { and DECLARE_END } are being set. That makes it possible to do the following in your source code (which this macro is really made up for):
#define ___ DECLARE_BLOCK #define ____ DECLARE_END
int f(void) {
char buffer[1024];
fgets(buffer, 1024, stdin);
___ int i; int ii = strlen(buffer);
for (i=0; i < ii; i++) {
fputc(buffer[i], stdout);
}____;
}
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Copyright © 2008 Guido U. Draheim guidod@gmx.de
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