What is the correct syntax for matching a constant in a regular expression? Here's the culprit: 
#!/usr/bin/perl;

use constant EXTENSION => '.txt';

die sprintf(
    'cannot match "%s" extension in "%s"', EXTENSION, $ARGV[0]
) unless $ARGV[0] =~ /EXTENSION$/;

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Thanks for your help.

In reply to constants within regular expression? by Anonymous Monk

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