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in reply to Re: A "but" operator.
in thread A "but" operator.

The but operator in Perl 6 is really a mixin operator underneath. Or looking at it the other way around, mixins already have a strong component of "I wish to contradict something someone said earlier".

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Re^3: A "but" operator.
by BrowserUk (Patriarch) on Sep 27, 2004 at 19:34 UTC

    Something like? 

    my Model $T = Ford( color => any( @colors ) ) but 'black';

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    Examine what is said, not who speaks.
    "Efficiency is intelligent laziness." -David Dunham
    "Think for yourself!" - Abigail
    "Memory, processor, disk in that order on the hardware side. Algorithm, algorithm, algorithm on the code side." - tachyon
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      I believe you are thinking of "except". </grammar-nazi>
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        No, I'm not.

        Anecdotal history suggests that Henry Ford's sales pitch for the Model T was "you can have any color you like; so long as it's black". </history_nazi> :)

        If I understand TimToady's statement of but being a mixin that allows you to contradict (override) early conditions or restraints, the analogy is that you take the guy's order for his model T, and allow him to specify whatever color he wishes; but you then override that by supplying a black one.

        Examine what is said, not who speaks.
        "Efficiency is intelligent laziness." -David Dunham
        "Think for yourself!" - Abigail
        "Memory, processor, disk in that order on the hardware side. Algorithm, algorithm, algorithm on the code side." - tachyon
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