Ion conditional compilation

[tjpalmer]

Unless I've missed, ion currently has no conditional compilation. Tying that with some built-in consts for OS and such would be great. This requires falling out to c whenever this is needed, which is one place in the current ion compiler.

An implementation for this might possibly be tied up with some implementation of macros, if any.

(As an aside, I'm mostly against general compile time code execution, because I'm afraid of people getting carried away with it. But it's technically a potential solution for these sorts of things, too.)

[Maykeye]

Unless I've missed, ion currently has no conditional compilation. Tying that with some built-in consts for OS and such would be great

It does exactly that already: if you append e.g. _win32 to filename, during module compilation file will be compiled only if you compiling for windows.

The name is kinda a misnomer as it applies to both 32 and 64 bit versions of windows. There are also suffixes for choosing architecture. Look in system_packages/builtin/

[tjpalmer]

Thanks for the tip! I'd managed to miss that this was a general feature in the compiler rather than specific handling for the builtins.

On not-necessarily-os issues, there's still a question of how to handle these kinds of things perhaps, though:

#ifndef MAX_PATH
#   if defined _MAX_PATH
#       define MAX_PATH _MAX_PATH
#   elif defined PATH_MAX
#       define MAX_PATH PATH_MAX
#   else
#       error "No suitable MAX_PATH surrogate"
#   endif
#endif