You should get out of the habit of unnecessarily quoting variables - it is bad habit. Here are a couple of corrections: 
my %snmp_options = (
   hostname    => $args->{h},
   retries     => $retries,
   # etc
);

# and 
$snmp_options{username} = $snmp_username;

[download]
Sure, using quotes works for those examples, but it is unnecessary and will one day lead to something like: 
package My::CGI;

use strict;
use CGI;

sub new {
   my $class = shift;
   my $foo   = 'bar';
   my $q     = CGI->new();
   my $self = {
      foo => "$foo",
      cgi => "$q",
   };
   return bless $self, $class;
}

package main;

use strict;

my $q = My::CGI->new();

print $q->{foo}, "\n";
print $q->{cgi}->a({href=>'http://foo.bar'},'some link'),"\n";

__END__
yields:
bar
Can't locate object method "a" via package "CGI=HASH(0x80f8a20)"
at ./foo.pl line 26.

[download]
Whoops! What happened? You literalized a reference. Try this code out, then go back and remove the unnecessary quotes inside the $self hash ref.

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)

In reply to (jeffa) 3Re: using return to create a module object by jeffa
in thread using return to create a module object by c

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.