... I want the program to report an error "warn" but continue and work with the correct argument.

In general, I find I have enough trouble when I try to guess what my programs should be doing; I certainly don't want my programs making those guesses!

However, in the spirit of giving good advice and then immediately undercutting it, you might look at Text::Levenshtein and related fuzzy string comparison modules; see Levenshtein distance. The strategy might be something like "look for all file names in a given directory with an L-D (or other match metric) less than a given threshold, then use the file name with the least distance if that name is unique". 

>perl -wMstrict -le
"use Text::LevenshteinXS;
 ;;
 my $tyop = 'twst.html';
 for my $try (qw(test.html testb.html)) {
   my $d = distance($tyop, $try);
   print qq{'$tyop' < $d > '$try'};
   }
"
'twst.html' < 1 > 'test.html'
'twst.html' < 2 > 'testb.html'

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In reply to Re: how to deal with incorrect command line argument by AnomalousMonk
in thread how to deal with incorrect command line argument by scripter87

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