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On 2016-06-28 21:32 +0200, Sean Conner wrote:
It was thus said that the Great Roberto Ierusalimschy once stated:
What I really meant was that with that macro you could perform the
cast on the pointer returned from malloc only when compiling as C++,
and avoid the cast in C, in order to "conform" to C best practices
[1] that advice against casting that pointer (as opposed as what you
should do in C++), as Sean said.

Let us see [1]:

* "It is unnecessary" - so are comments, identation, etc.

* "It can hide an error, if you forgot to include <stdlib.h>." - This
could be a valid argument 20 years ago (K&R C). If you do not use
something like -Wstrict-prototypes and -Wmissing-prototypes, something
is very wrong, as every single function call in your program could hide

* "It adds clutter to the code" - A macro would add even more "clutter".

* "It makes you repeat yourself" - So does a macro.

  So if you are adding the casts because C++ requires them, then you should
also remove all NULLs since C++ practically rejects those.

  -spc (and to further compound the issue, you should therefore define
	nullptr to be NULL when compiling with a C compiler, because you
	know ... C is a second class citizen ... )

Edge cases with overload resolution aside (which Lua, being written in the C subset of C++, is not affected from), there is no problem with using NULL in C++. In fact, before C++11 introduced nullptr, it was common practice, so I wouldn't even say that NULL is "C style".