While I would not recommend it, $a and $b are only special in that they are predeclared and used by sort. Otherwise, you can use them like any other package variable:

sub mysort (&@)
{
    my $coderef = shift;
    while (@_ > 1)
    {
        $a = shift;
        $b = $_[0];
        my $c = $coderef->();
        print " $c";
        # do sorting
    }
    print "\n";
}

mysort { $a <=> $b } qw(1 3 2);

[download]

But, it is a bad idea to use $a and $b except with sort

But, could use 2 other variables. Just have to declare them.

In reply to Re^4: Prototype like sort()? by RonW
in thread Prototype like sort()? by perlancar

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