meson/docs/markdown/snippets/compiler_has_define.md

## Compilers now have a `has_define` method

This method returns true if the given preprocessor symbol is
defined, else false is returned. This is useful is cases where
an empty define has to be distinguished from a non-set one, which
is not possible using `get_define`.

Additionally it makes intent clearer for code that only needs
to check if a specific define is set at all and does not care
about its value.
Add compiler.has_define Adds a new method to the compiler object, has_define. This makes it possible to check if a preprocessor macro/define is set or not. This is especially helpful if the define in question is empty, for example: #define MESON_EMPTY_DEFINE This would yield the same results as a missing define with the existing get_define method, as it would return an empty string for both cases. Therefore this additional method is needed. 1 year ago			## Compilers now have a `has_define` method

			`This method returns true if the given preprocessor symbol is`
			`defined, else false is returned. This is useful is cases where`
			`an empty define has to be distinguished from a non-set one, which`
			is not possible using `get_define`.

			`Additionally it makes intent clearer for code that only needs`
			`to check if a specific define is set at all and does not care`
			`about its value.`