It's a decent attempt especially for a first time ;-)

I took some pleasure in decyphering your code to derive at the spoiler. You've used a number of interesting tricks to obfuscate the code.

Some of the discovered obfuscation tricks:
1. use of => in place of ;
2. use of non standard delimiters in search and replace regexp (s///)
3. Hiding $_ and __DATA__ input handle behind the *_ typeglob.
4. Using left shift bitwise operation to calculate N/2 (e.g. N >> 1 instead of just N/2).
5. and some other ;-)


For the simplified version of the JAPH look below: 
#!perl -s

$/ = undef;
my $data = <DATA>;

# remove all non numeric characters from $_
$data =~ s/[^\d]//g;

# take 3 digits at a time and convert them to a char
$data =~ s/(\d{3})/chr($1)/egx;
@data = split('', $data);

my @letters;
for (my $i = 1; $i <= @data / 2; $i++) {
    push @letters, $data[$i] ^ $data[-$i];
}

print join('', @letters);

__DATA__
             042123185208084070254140
            01                      01
           700   Combat Squirrel's  772
          4017                      1061
         17923      f i r s t       71340
        190970                      421301
       0408004       J A P H        4064086
      12005007                      30590112
     2706606512724413622702921714903722210122
    6***1*5*9*1*0*2*0*3**2*1*6*3*2*0*4*0*4***9

[download]


update: Front-paged this one as I felt it deserves it.

_____________________
"We've all heard that a million monkeys banging on a million typewriters will eventually reproduce
the entire works of Shakespeare. Now, thanks to the Internet, we know this is not true."

Robert Wilensky, University of California

In reply to Re: YAJAPH - Yet Another JAPH by vladb
in thread YAJAPH - Yet Another JAPH by CombatSquirrel

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