Maybe the perl i'm using is modified as it seems to work correctly.

No. You can see how its broken by giving a different extension, like this

#!/usr/bin/perl --
use Test::More ;
for my $ext ( qw/ jpg gif bmp PNG / ) {
    my $isItTrue = int( $ext eq "jpg"||"gif"||"bmp");
    is( $isItTrue, 1, "$ext" );
}
Test::More::done_testing();
__END__
ok 1 - jpg
not ok 2 - gif
#   Failed test 'gif'
#   at - line 5.
#          got: '0'
#     expected: '1'
not ok 3 - bmp
#   Failed test 'bmp'
#   at - line 5.
#          got: '0'
#     expected: '1'
not ok 4 - PNG
#   Failed test 'PNG'
#   at - line 5.
#          got: '0'
#     expected: '1'
1..4
# Looks like you failed 3 tests of 4.
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I thought CGI caused undue overhead?

If the overhead bothers you, use CGI::Simple, or better yet, get a better webserver, like plackup

I highly recommend you start with beginning-perl book, or Tutorials

Saved me the testing time, thanks :) I'd have used real life examples, hitting the webserver to see if things worked properly, taking much more time to debug. I definately am looking into better web servers, but i'm only planning atm. Until i'm going live, I don't need to worry about overhead, but its best to keep it low from the start. Thank-you again, you've answered everything I needed to know and more :) Happy holidays!

PS: Yes, i've checked out some of those writings and continue to read through them

There isn't in existence

See also B::Deparse

$ cat junk
int( $ext eq "jpg"||"gif"||"bmp")

$ perl -MO=Deparse,-p junk
int(((($ext eq 'jpg') or 'gif') or 'bmp'));
junk syntax OK

$ perl -le " print int( 'jpg' eq 'jpg' ) "
1

$ perl -le " print int( 'gif' ) "
0

$ perl -le " print int( 'bmp' ) "
0
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