I suggest: 
my @datafiles = glob("$basepath$ARGV[0]/$ARGV[1].[dD][aA][tT]");

[download]

It takes care of the special cases and eliminates the grep.

Figuring out why it eliminates the grep is an exercise for the reader. :-) Hint: You might need to use man instead of perldoc. . . 

-sauoq
"My two cents aren't worth a dime.";

In reply to Re: Re^2: Upper / Lower case extensions by sauoq
in thread Upper / Lower case extensions by Cockneyphil

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