Alright, let us say that I have a file, let us call it input.txt. This file reads as follows: 
This is the time: $variable

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Now let us say that I right the following script: 
#!/usr/bin/Perl -w

use strict; # as always

open ( FILE, "input.txt" ) or die ( "input.txt: $!" );

my $variable = localtime;

while (<FILE>) {
  print $_;
}

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This script is, of course, spectacularly useless. One might think that it would print "This is the time: -insert time here-". One would be wrong. It prints "This is the time: $variable".

Obviously, I could just write the script to say print localtime;, but that isn't what I'm really trying to do. I just need, in general, the ability to interpolate one level deeper. So the question I have for you, O monkish fonts of everlasting wisdom, is this:

How do I convince Perl to evaluate the values of the variables that are contained in a string that I read from a file?

Some people drink from the fountain of knowledge, others just gargle.

In reply to Digging interpolation deeper by DeusVult

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