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    SubjectRE: [RFC][PATCH] A generic boolean
    Date
    Someone showed code like

    _Bool foo = 42;

    and if we were to make the compiler warn about it that would mean we are
    basically trying to change/manipulate the standard (I'm guessing). It's
    probably not in the standard because it's such a moot point. However if we
    were to use

    if(foo)
    {
    ...
    }

    we'd see it was true. That's because
    FALSE == 0
    and
    TRUE == !FALSE (i.e. any value that isn't 0)

    from the compiler's standpoint. Function that return 'true' for an integer
    type (as opposed to a C++ standard-type bool) should be tested like

    if(SomeFunction())

    or
    if(!SomeFunction())

    instead of testing for equality

    if(SomeFunction() == TRUE)
    of
    if(SomeFunction() == FALSE)

    as the former (IMO) is as readable, if not more readable as the latter, and
    it's likely to get optimised better. That and someone might give true AND
    return a status by returning neither 0 or 1, in which case

    if(... == TRUE)

    would fail, as TRUE == 1.

    And just as a note, you really should read the documentation (at least once)
    for any function you use, and therefore know if it returns {FALSE, TRUE, ...
    , TRUE} or {OK, ERR1, ERR2, ..., ERRn}

    > > If this is the case, then wouldn't "long" be preferable to "int"?

    Meh, it's all the same. I don't think 3 wasted CPU cycles is going to worry
    anyone too much. Hell, sometimes int IS long, though I might be wrong there.


    P.S. First post! Hello everybody.
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