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How would I replace the string 'Red1' with $Red[1]?

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Contributed by draco_iii on Jun 29, 2000 at 17:29 UTC
Q&A  > regular expressions


Description:

I have 8 common looking varibles and I need to check for them all in one line of a file to change the font color. But when I ran the following all it did was exactly what I told it to do. it replaced $red1 with $red1 when what I wanted it to do was replace $red1 with "black" and $red2 with "red".
for ($i = 1; $i < 9; $i++) { $_ =~ s/\$red$i/\$red$i/sg; + }

Answer: How would I replace the string 'Red1' with $Red[1]?
contributed by QandAEditors

Use an array (or a hash). What you're trying to do now smells like symbolic refrences, which are just yicky (to use the technical term ) and make your code harder to write and maintain.

You will also need to use the /e modifier (which causes Perl to eval the right-side as an expression).

use strict; my @red; $red[1]='black'; $red[2]='red'; $line =~ s/\$red(\d)/$red[$1]/ge; +
Answer: How would I replace the string 'Red1' with $Red1?
contributed by chipmunk

Actually, it is not necessary to use the /e modifier in the QandAEditors' substitution, because without /e the right-hand side of a substitution interpolates just like a double-quoted string.

$line =~ s/\$red(\d)/$red[$1]/g;

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