question about naming variables/functions

This is a discussion on question about naming variables/functions within the C Programming forums, part of the General Programming Boards category; what does it mean if u begin a variable/function name with __ (an underscore or 2)?...

  1. #1
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    question about naming variables/functions

    what does it mean if u begin a variable/function name with __ (an underscore or 2)?

  2. #2
    ATH0 quzah's Avatar
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    It means you've started it with two underscores...


    Quzah.
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  3. #3
    End Of Line Hammer's Avatar
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    It also means you're breaking, or close to breaking, a C standard ruling. Read about them here .

    Personally, I avoid naming variables that begin with an underscore.
    When all else fails, read the instructions.
    If you're posting code, use code tags: [code] /* insert code here */ [/code]

  4. #4
    Code Goddess Prelude's Avatar
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    >It also means you're breaking, or close to breaking, a C standard ruling.
    Or to be more precise, you're most definitely using an identifier that is reserved in all cases by the implementation:
    7.1.3 Reserved identifiers
    ...
    -- All identifiers that begin with an underscore and either an uppercase letter or another
    underscore are always reserved for any use.
    >Personally, I avoid naming variables that begin with an underscore.
    A good habit to get into. Much easier than remembering the complex rules concerning reserved identifiers.
    My best code is written with the delete key.

  5. #5
    End Of Line Hammer's Avatar
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    >>you're most definitely using an identifier that is reserved in all cases by the implementation<<
    Well... nit picking the nit picker.... a name like _myvar isn't reserved according to that rule But let's not get too deep.

    Welcome back, btw.
    When all else fails, read the instructions.
    If you're posting code, use code tags: [code] /* insert code here */ [/code]

  6. #6
    Code Goddess Prelude's Avatar
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    >Well... nit picking the nit picker.... a name like _myvar isn't reserved according to that rule
    That's true, the next rule that I didn't paste explains how the single underscore works:
    All identifiers that begin with an underscore are always reserved for use as identifiers
    with file scope in both the ordinary and tag name spaces.


    >Welcome back, btw.
    Thanks.
    My best code is written with the delete key.

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