Preprocessor directives

This is a discussion on Preprocessor directives within the C Programming forums, part of the General Programming Boards category; hey guys i came across this Code: #define LCD_E(x) ((x) ? (IOSET1 = PIN_E) : (IOCLR1 = PIN_E) ); i ...

  1. #1
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    Preprocessor directives

    hey guys i came across this

    Code:
    #define LCD_E(x)              ((x) ? (IOSET1 = PIN_E)  : (IOCLR1 = PIN_E) );
    i know that it is macro expansion but wat does the expression in the brackets mean?

  2. #2
    C++ Witch laserlight's Avatar
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    It is the ternary operator. If x evaluates to true, the result of the operation is (IOSET1 = PIN_E), otherwise it is (IOCLR1 = PIN_E). Incidentally, the semi-colon at the end of the macro looks like it should not be there.
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  3. #3
    Code Goddess Prelude's Avatar
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    On a completely unrelated note:

    [] = Brackets
    {} = Braces
    () = Parens (parentheses)

    As it is, one can figure out what you meant, but saying "brackets" when you mean "parens" can be confusing if both are present in the expression.
    My best code is written with the delete key.

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