Re: Command line globber/tokenizer library for C?

Michael S <already5chosen@yahoo.com> writes:

[...]

Since I am not accustomed to the functional programming style, for
me even a boring variant [not shown] is way too entertaining.  I
prefer mundane (untested, could be buggy):
>
static
const char* collect_word(const char *s) {
  _Bool w = 0;
  char c;
  while ((c = *s) != 0) {
    if (!w && is_space(c))
      break;
    if (c == '"')
      w = !w;
    ++s;
  }
  return s;
}
>
void words_do(const char *s, Gopher go ){
  char c;
  while ((c = *s) != 0) {
    if (is_space(c)) {
      ++s;
    } else {
      const char *r = s;
      s = collect_word(s);
      go->f(go, r, s);
    }
  }
}

If writing in an imperative-rather-than-functional style, I would
likely gravitate toward something like this:


   static  const char *process_word( const char *, Gopher );

   void
   words_do( const char *s, Gopher go ){
      char   c;

      while(  c = *s++  ){
         if( ! is_space(c) )  s = process_word( s-1, go );
      }
   }

   const char *
   process_word( const char *r, Gopher go ){
      const char *s = r;
      _Bool       q = 0;

      do  q ^= *s++ == '"';  while(  *s && (q || !is_space(*s))  );

      return   go->f( go, r, s ),   s;
   }


which seems to result in slightly better generated code than my
functional version, in a few spot checks using gcc or clang
under various -O settings (-Os, -O2, -O3).