in reply to Assignments for Subroutines

The following is my version of part 1. You may find use diagnostics useful if you are new. 
#!/usr/bin/perl
use strict;
use warnings;
use diagnostics;
        #more verbose feedback
        #useful for debugging

my@num = (1..10);

sub printeven{
        my @given=@_; #pull in list given later: printeven(@list)
        my @evens;
        for (@given){
                unless($_%2){ #unless odd
                        push(@evens,$_); #add number to @evens
                }
        }
        $,=", "; #change list delimiter for fancy printing
        print @evens;
        print "\n"; #newline
        $,=""; #change list delimiter back before it is a problem
}

printeven(@num); #call sub with list of numbers 1-10

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Re^2: Assignments for Subroutines
by nemesdani (Friar) on Sep 27, 2012 at 10:29 UTC 
    $,=", "; #change list delimiter for fancy printing
print @evens;
print "\n"; #newline
$,=""; #change list delimiter back before it is a problem

    [download]
    That could be written as 
    {
local $,=", ";
print @evens;
print "\n"; #newline
}

    [download]
    No need to change it back, less possibility of an error. My 2 cents.


    I'm too lazy to be proud of being impatient.
[reply]
[d/l]
[select]

      Indeed. Especially because this...

      $,=""; #change list delimiter back before it is a problem

      [download]

      ... changes the list delimited "back" to the empty string, when we never checked that it started off as the empty string to begin with!

      perl -E'sub Monkey::do{say$_,for@_,do{($monkey=[caller(0)]->[3])=~s{::}{ }and$monkey}}"Monkey say"->Monkey::do'
[reply]
[d/l]
      That is better. You have my +1
[reply]

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