I have lines in a file that can contain dynamic variables in the form ${var_name}. In another file, the dynamic variables are defined as var_name = var_value. I created a hash, such that the key is var_name and the value is var_value. Everything on the left side of the '=" sign is converted to lowercase before being used as a key for consistency.

My question is, what is the best way to find all dynamic variables in a line and swap them with their respective value. I have it currently as a two step problem, but the second, and probably easy part, is giving me issues. 
$line =~ s/\$\{\S+\}/\l$1/g;   # not sure if escaping the {'s is neces
+sary.

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Now I can say what I need to do in English, but after a long week, my brain won't give me the Perl code. I need to take $1 and use it in $dynamic_variables{$1} to replace the lefthand side of the s///.

20040414 Edit by BazB: Changed title from 'swapping "dynamic" variables'

In reply to replacing "dynamic" variables by emilford

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