| /* |
| * Each iteration of the scanning of "SCAN()" re-evaluates the recursive |
| * B->A->B expansion. |
| * |
| * Did I already mention that the C preprocessor language |
| * is a perverse thing? |
| */ |
| |
| #define LP ( |
| |
| #define A() B LP ) |
| #define B() A LP ) |
| |
| #define SCAN(x) x |
| |
| A() // B ( ) |
| SCAN( A() ) // A ( ) |
| SCAN(SCAN( A() )) // B ( ) |
| SCAN(SCAN(SCAN( A() ))) // A ( ) |
| /* |
| * check-name: Preprocessor #3 |
| * check-description: Sparse used to get this wrong, outputting A third, not B. |
| * check-command: sparse -E $file |
| * |
| * check-output-start |
| |
| B ( ) |
| A ( ) |
| B ( ) |
| A ( ) |
| * check-output-end |
| */ |
