Okay, here's my attempt at this one, it should be slightly more efficient than using arrays, but you really should benchmark that...:

#!/usr/bin/perl -w
use strict;
unless ($ARGV[0] eq '-lc' || $ARGV[0] eq '-uc' ){
    die "usage: lcuc [-uc | -lc] file\n";
}

my $op = substr(shift @ARGV, 1, 2);

while(<>){
    no strict 'refs';
    print &{$op}($_)
}

sub lc{ lc shift }
sub uc{ uc shift }

[download]

TMTOWTDI Update (as suggested by tilly)

I'll admit that this one is cleaner than the above code. :)

#!/usr/bin/perl -w
use strict;

my %ops = (
    'lc' => sub {lc shift },
    'uc' => sub {uc shift },
);


my $case = shift @ARGV;
unless (exists $ops{$case}){
    die "usage: lcuc [", join(' | ', keys %ops), "] file\n";
}
while(<>){
    print $ops{$case}->($_);
}

[download]
<kbd>--
my $OeufMayo = new PerlMonger::Paris({http => 'paris.mongueurs.net'});</kbd>

In reply to Re: More efficient munging if infile very large by OeufMayo
in thread More efficient munging if infile very large by ybiC

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