There are at three options. First, write a regex that scans your text for variables, replacing them with the values. It's much, much easier to use a hash for this: 
my $text = "Insert $id here!\n";
my %values = ( id => 10 );
$text =~ s/\$(\w+)\b/$values{$1}/g;
print $text, "\n";

[download]
That's untested, but can't be too far off. This is a simple solution that works for simple problems. It's possible to craft a much nicer regex to catch boundary conditions, but it's difficult.

The second option is an awful abuse of eval I like to call Double Interpolation of a String . I wouldn't recommend it, if you can avoid it.

The third option is to use a templating mechanism from the CPAN, like Text::Interpolate or Text::Template. This is by far the most powerful and safe mechanism. If you're going to be doing this often, time invested in learning one of these modules will pay off nicely.

In reply to Re: Eval'ed data loaded from a file? by chromatic
in thread Eval'ed data loaded from a file? by dakotas

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