Dynamically name the variable and get it's value from Module

sriram83.life has asked for the wisdom of the Perl Monks concerning the following question:

I have a script as follows:

#!/usr/bin/perl

use Mailer;
my $circle = Chennai;
my $file = "TO_" . "$circle";

print "MailDetails : $Mailer::$file\n";
[download]

And Module "Mailer" as follows:

Package Mailer;

our $TO_Chennai = q(sriram.perumalla@ness.com);
1;
[download]

Now, when i print $Mailer::$file , I should get "sriram.perumalla@ness.com".But, it prints nothing. Can any one suggest me how to get the value of the variable in the perl script which is dynamically named and it's variable value is in other module.

Regards,

Sriram

Comment on Dynamically name the variable and get it's value from Module Select or Download Code

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Re: Dynamically name the variable and get it's value from Module by Corion (Patriarch) on Apr 28, 2015 at 13:35 UTC
Please don't do that. Use a hash that stores all the adresses: `package Mailer; our( %TO ); $TO{ Chennai }= 'sriram.perumalla@ness.com'; package main; print $TO{ Chennai };` [download] If you want to learn about why it's a bad practice, read http://perl.plover.com/varvarname.html and the two follow-up parts.	[reply] [d/l]
Re: Dynamically name the variable and get it's value from Module by Laurent_R (Canon) on Apr 28, 2015 at 17:43 UTC
If you had the `use strict;` pragma at the beginning of your script (and you should), you would get a first error at compile time: `Bareword "Chennai" not allowed while "strict subs" in use at ...` [download] And, once corrected by adding quote marks, you would get a second error at runtime: `$ perl -e ' > use strict; > use warnings; > > our $TO_Chennai = "foobar"; > > my $circle = "Chennai"; > my $file = "TO_" . "$circle"; > print $$file;' Can't use string ("TO_Chennai") as a SCALAR ref while "strict refs" in + use at -e line 9.` [download] Symbolic references were once (before Perl 5, i.e. more than 20 years ago) the only way to do certain types of things similar to what is sometimes done in shell scripting, but they are really frown upon in today's Perl programming. They are really a source of errors often difficult to track. To the point that they are forbidden with strictures (there are still there with no strictures only to preserve compatibility of very old programs). Use a hash instead. Do yourself a favor: `use strict;` and `use warnings;`, and the compiler will tell you immediately about many of your mistakes, typos, etc., and you'll gain a lot of time. Je suis Charlie.	[reply] [d/l] [select]
Re: Dynamically name the variable and get it's value from Module by hdb (Monsignor) on Apr 28, 2015 at 13:34 UTC
~~It should be~~ `$Mailer::file` [download] Update: Forget my reply. I misread the code and the question.	[reply] [d/l]