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macro

what is use of macro in c language ?
Aug 5 '12 #1

✓ answered by weaknessforcats

Suppose your program needed a "maximum allowed value" of 10. You could hard-code 10's all over your code and tings would wrok fine. Then if you needed to change the maximum value to 25 you could edit all of your code and manually change he 10 to 25.

Or you could use a macro:

Expand|Select|Wrap|Line Numbers
  1. #define MAXVALUE 10
Now you hard-code MAXVALUE instead of 10. Then when you need to change the 10 to 25, you just change the #define and rebuild your code.

You can also use a #define to represent code. Plenty of examples for this on the web.

2 1485
weaknessforcats
9,208 Expert Mod 8TB
Suppose your program needed a "maximum allowed value" of 10. You could hard-code 10's all over your code and tings would wrok fine. Then if you needed to change the maximum value to 25 you could edit all of your code and manually change he 10 to 25.

Or you could use a macro:

Expand|Select|Wrap|Line Numbers
  1. #define MAXVALUE 10
Now you hard-code MAXVALUE instead of 10. Then when you need to change the 10 to 25, you just change the #define and rebuild your code.

You can also use a #define to represent code. Plenty of examples for this on the web.
Aug 5 '12 #2
thanks a lot for this ans.
Aug 5 '12 #3

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