IF / ELSE / ENDIF macros for M4

Greetings,

I heard a long time ago that CPP was derived from M4, and read that a 
few folks including myself have looked for IF / ENDIF type macros to use 
on other projects. CPP is not ideal in that it wants to take extra steps 
like tokenizing the source.

Here is a post from someone else looking:

https://stackoverflow.com/questions/50549946/conditional-compilation-interpretation-using-m4/66978338#66978338

So not finding anything like this, I wrote some that seem to work pretty 
well. Here they are:

http://www.eugeneweb.com/wiki/Sites/M4Macros

I defined the names without the #'s eg. IF, ELSE, ENDIF, etc... Also M4 
requires parentheses to hold the arguments where CPP does not (at least 
for most of these). I also added a selective invoke, to protect macros 
with side effects from invocation in an unselected block.

I was wondering if they pass muster, if the devs might consider 
including them or something similar in M4's list of examples. 
<https://stackoverflow.com/posts/66978338/timeline>

     Best,
     Clif