Be aware that regular expressions are case sensitive; you are looking for "foo" but the string contains "FOO". Also, you seem to be matching against $_ and applying substr to it but your code doesn't show where you initialise it. I'm finding your question a little difficult to understand but perhaps captures and lc would be applicable.

knoppix@Microknoppix:~$ perl -Mstrict -wE '
> my $var1 = q{some_stuff_FOO};
> my $var2 = q{more_gubbins_BAR};
> my $var3 = q{lose_this_LOST};
> 
> my $path = join q{/},
>    q{},
>    map { my( $ext ) = m{([A-Z]+)$}; lc $ext } $var1, $var2, $var3;
> say $path;'
/foo/bar/lost
knoppix@Microknoppix:~$

[download]

I hope I've guessed correctly and this is helpful.

Cheers,

JohnGG

In reply to Re: Building Paths without Regex by johngg
in thread Building Paths without Regex by rehann

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