Closures are cool, but I dont really see any practical or theoretical benefit to what you are tutoring: 
package Max;

sub new {
    my $class = shift;
    my $max   = undef;
    return bless \$max, $class;
}

sub compare{
    return $_[1] > $_[2];    
}

sub max{
    my $self = shift;
    for ( @_ ) {
        $$self = $_ if $$self == undef || $self->compare($_,  $$self);
    }
    return $$self;
}

package StringMax; our @ISA = ('Max');

sub compare {
    return length($_[1]) > length($_[2]);
}

package main;

my $max= new StringMax();
while ( <FH> ) {
    chomp;
    $max->max($_);
}
my $long_str = $max->max();

[download]
The same functions, the same number of lines - better organized for applying to real problems.



time was, I could move my arms like a bird and...

In reply to Re: How A Technique Becomes Over-rated by Ctrl-z
in thread How A Function Becomes Higher Order by Limbic~Region

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