Re: stack module

[Marc Nieper-Wißkirchen]

Hi Bruno,

I am finally finishing my work on the stack module.

Am Do., 23. Juli 2020 um 12:36 Uhr schrieb Bruno Haible <bruno@clisp.org>:

[...]

> This is perfectly acceptable for Gnulib. It has debuggability and type safety.
>
> You have precedent e.g. in lib/diffseq.h and lib/aligned-malloc.h.
>
> You can even omit the 'GL_' prefix from the macro names. The user can #undef
> the macros after including the file; therefore there is nearly no risk of
> collision with macros defined by other code.

After I have given it a bit more thought, I see a different type of
collision possibility, namely if some header file uses the stack
header file. It will leak the macro names. Assume that the stack
module accepts the macro name ELEMENT for the element type. A
hypothetical header for the frob type may be implemented as:

#ifndef FROB_H
#define FROB_H
...
#define ELEMENT int
#define STORAGECLASS static inline
#include "stack.h"
...
struct frob
{
  stack frob_stack;
  ...
};
...
#endif /* FROB_H */

Now, user code cannot do:

#define ELEMENT hydrogen
#include "frob.h"
...

(The ELEMENT definition in the first line could in fact be exported by
some other header file.)

Therefore, I think I prefer to use prefixed names.

Cheers,

Marc