I would much agree on the remarks made by other monks, to use a hash for your config vars is a much cleaner and safer approach.

Having said that, your idea of using an eval can work as per below example. Just keep in mind that:

• eval runs as a nested block, therefore any variables declared within eval are lost once eval is done. Hence you you need to declare your variables before using them in the eval.
• make sure that your eval cannot be abused thru evil data in a configfile. So check all input before you use it in eval, make sure to single-quote string so that they do not get interpreted, etc etc.

#!/usr/bin/perl
use warnings;
use strict;

my @accepted_vars = qw( myvar1 myvar2 );
my $myvar1; # must declare variable beforehand!
my $myvar2;

my @lines = <DATA>;
chomp @lines;

foreach (@lines) {
    if  (  /^\s*(.*?)\s*=\s*(.*)/  &&
          grep $1 eq $_ , @accepted_vars
        ) {
        eval '$'."$1 = '$2'";
        warn "eval failed: $@\n" if $@;
        }
    else {
        warn "Illegal config var '$1'\n";
        }
    }

print "myvar1 = '$myvar1'\n",
      "myvar2 = '$myvar2'\n";

__DATA__
myvar1 = foo
myvar2 = bar
evil_var = foo
[download]

Output from program is:

Illegal config var 'evil_var'
myvar1 = 'foo'
myvar2 = 'bar'
[download]

---

---

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! —

• How do I compose an effective node title?
• How do I post a question effectively?
• Markup in the Monastery

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:
	&		&
	<		&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.