jestermax Member Posts: 1064 From: Ontario, Canada Registered: 06-21-2006 |
hey, i've been seeing a lot of #pragma once in header files lately. is there an advantage/disadvantage to using that over the "#ifndef blah, #define blah, #endif" structure? |
dartsman Member Posts: 484 From: Queensland, Australia Registered: 03-16-2006 |
I actually now put both... just as the compiler can discard the #pragma once if need be... There would be no performance boost at run-time (obviously  ), however possibly could do something to help with compile times, though would be different on each compiler.There is no harm (that I know of) in putting both. ------------------ [This message has been edited by dartsman (edited February 22, 2007).] |
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jestermax Member Posts: 1064 From: Ontario, Canada Registered: 06-21-2006 |
ok, i just looked it up: "#pragma once" is microsoft only (as i suspected). if you want portable code then use the "ifndef" clause instead. so sad  #pragma once is so much faster to type then #ifndef EXTREMELY_LONG_CLASS_NAME |
SSquared Member Posts: 654 From: Pacific Northwest Registered: 03-22-2005 |
Woah! What a trip. Thanks for the info Jestermax. I think pragma once was introduced with VS 2003. I thought, "This is SO cool and easy." Now I may think twice about using it. |
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dartsman Member Posts: 484 From: Queensland, Australia Registered: 03-16-2006 |
yeah, I still believe that you can have it in your code on other compilers though... just that it will disregard it on some compilers... Anywho, it would be good to find out if other compilers will throw a warning on it or not. ------------------ |