Thread: What does this mean?

Nope, you're quite correct. Anything that starts with a # is a command to the preprocessor. In this case, it will cause the preprocessor to find-and-replace all occurences of eq(A, B) with (A == B), whatever A or B is.

QuantumPete

Yes, all #defines are "replacement macros" [but they CAN be used to see if they are simply defined or not defined too].

In this case, you'd have some code like this:

Code:

T x, y;
... 

if (eq(x, y)) ... 
...

Which would compile as:

Code:

...
if (x == y) ... 
...

But if you don't use the macro, it does "nothing" [assuming, also, of course nothing else uses it].

--
Mats

But might I add that you be careful with macros? The above example is bad macro, because all it does is essentially create a "new language within a language," basically creating new syntax which will confuse other programmers.
Macros are also very hard to debug, so use them sparingly and well.
That's all

Originally Posted by Elysia

But might I add that you be careful with macros? The above example is bad macro, because all it does is essentially create a "new language within a language," basically creating new syntax which will confuse other programmers.
Macros are also very hard to debug, so use them sparingly and well.
That's all

Yes, that particular one looks like it's trying to sort of use Fortran style comparisons (which in early fortran use .ne. and .eq. for example).

--
Mats