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[std-proposals] Macro scope

From: BAMBYK <uravasinski_at_[hidden]>
Date: Fri, 1 Sep 2023 08:34:29 +0300
This is similar to a regular namespace but with macros. Libraries does
often use macros and it is usually done by a large of capital letters with
the identificator of library at the beginning (boost for example):
BOOST_<macro meaning>

But a something similar to namespace can be used for grouping such kind of
# scope BOOST
 # define macro1
 # define macro2
 # define one 1
# endscope
 // apply macro 'one' from the scope BOOST
 // do some preprocessor conditions
 # ifdef BOOST.one
  std::cout << "A scope BOOST has macro 'one'." << '\n';
 # endif

Or if a macro is used in settings purpose

# scope BOOST
here we define a scope with specific macro that is used in boost library as
setting (for example)
 # define setting1
# endscope

// inside boost library

# scope BOOST
 // other macros of BOOST library
 # define setting2
# endscope

   first scope BOOST and second are concatenated and in result the BOOST
consists of:

   So this way we've defined a custom setting for that scope

# ifdef BOOST.setting1
  // do something
# endif

These scopes can be used for other purposes too and not for library only as
they let user group their macros better. The benefit is also it is not
wholly consists of the capslock so is easer to read.

Received on 2023-09-01 05:34:42