Scoped cleanup

+ <stdio.h>
# Cleanup is just a macro: open, run the indented body, always close.
@m with_file($f, $path, $body:block)
  for $f: *FILE = fopen($path, "r"); $f; $f = (fclose($f), (FILE *)0)
    $body
f count(path: str) i32
  n:=0
  @with_file(f, path)
    while fgetc(f) != EOF
      ++n
  < n
f main()
  printf("bytes: %d\n", count("/dev/null"))
  printf("missing: %d\n", count("/no/such/file"))
  < 0

#include <stdio.h>

int count(const char *path) {
    int n = 0;
    for (FILE *f = fopen(path, "r"); f; f = (fclose(f), (FILE *)0)) {
        {
            while (fgetc(f) != EOF) {
                ++n;
            }
        }
        ;
    }
    return n;
}

int main(void) {
    printf("bytes: %d\n", count("/dev/null"));
    printf("missing: %d\n", count("/no/such/file"));
    return 0;
}