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in reply to Is it possible to store an arthimetric operator in a variable?

Sure: 
sub _eq($$){ $_[0] == $_[1] ? 1 : 0 }
sub _ne($$){ $_[0] == $_[1] ? 0 : 1 }
my $op = \&_eq; 
print $op->( 1, 2 ) ? 'EQ' : 'NEQ'";

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Edit: mrborisguy beat me to this answer while I was contemplating using tie to do it.
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Re^2: Is it possible to store an arthimetric operator in a variable?
by ikegami (Patriarch) on Jul 19, 2005 at 14:46 UTC

    You shouldn't use prototypes unless necessary, because of their side-effects. In this case, the prototype isn't even being checked because you're using a reference to the function.

    Read more... (382 Bytes)

    And why bother with ?1:0 and ?0:1 since == already returns a boolean value.

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      You are correct that the code isn't using the prototypes or requires the 1:0. I used them both, however, to be very clear to our anonymous reader what it was the code was doing. Also, I used 1:0 because I don't like using undef as a boolean false; it's not relevant here, but I find that 0 as false makes debugging easier which has led to this habit.
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        Boolean false isn't undef. Notice the lack of warnings in the following snippet: 
        >perl -we "print(1==2)"

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Re^2: Is it possible to store an arthimetric operator in a variable?
by Adam (Vicar) on Jul 19, 2005 at 17:27 UTC
    For those curious, this is how I might do it using tie.
    Read more... (2 kB)
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