> My understanding of an iterator function

here an example of a generator creating an iterator and using closure variables.

use strict;
use warnings;

sub gen_range_step {
    my ( $start,$stop,$step ) = @_ ;

    my $current = $start;

    return sub {
        my $val   = $current;
        $current += $step;
        return $val if $val <=$stop;
        return;
    }
}

my $iter = gen_range_step(5,20,4);

while ( my ($val) = $iter->() ) {
    print "$val\n";
}

[download]

    
C:/Strawberry/perl/bin\perl.exe -w d:/tmp/pm/generator_iterator.pl 
5
9
13
17

Compilation finished at Sat Nov 13 21:18:20

[download]

> but keep in mind I studied engineering and not computer science

I studied mathematics and some CS, and FP was never mentioned.

Cheers Rolf
(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery

In reply to Re^6: What technical benfits perl offers over python + few more questions. (generator/iterator/closure) by LanX
in thread What technical benfits perl offers over python + few more questions. by Anonymous Monk

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