How does C++ assert access input as a string

Question

I'm relatively new to C++, so go easy. When assert gets something that evaluates to false, I get this in the terminal:

test: test.cpp:185: void test(): Assertion `actual == testing` failed.
Aborted

How does assert get the input as a string? Wouldn't assert just "see" true or false?

possible duplicate of [How to use Macro argument as string literal?](http://stackoverflow.com/questions/10507264/how-to-use-macro-argument-as-string-literal) — Daniel A. White, Sep 23 '15 at 01:01
What does your assert statement look like, add the code to the question -- the answer lies in that information — Soren, Sep 23 '15 at 01:01
I'd delete it since this question doesn't add much more to what is already answered. — Michael Petch, Sep 23 '15 at 01:03

score 1 · Accepted Answer · answered Sep 23 '15 at 01:03

You can implement your own version of assert as a macro. This may or may not be how your compiler implements it.

Since #something will expand to a stringified version of it, you can do:

#define str(s) #s
#define assert(x) if(!x) {print(".... Assertion `" str(s) "` failed.")

See GCC docs for more information.

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