It just looks like the results of the eval are being printed to the screen.

It makes no sense for that eval to do so, and I can't reproduce it. The following produces no output to the screen. 

use strict;
use warnings;

my $test_crypt = "NK JNK YJ YAK ZPCCTK GDKQ YAK YNJ NJVQY PUSKUYPJUQ J
+R AMZGUPYL - VJZGUYPX TJSK GUC DMUOJNCKV. -- GUCVK ZGMVJPQ";
my $key        = 'something';
my $word       = 'PUSKUYPJUQ';

eval "\$test_crypt =~ tr/$key/$word/";

[download]

So far, we've only received unverifiable claims on your part. Please provide us the means of reproducing your results.

The code is too convoluted, long and poorly written to post

Yet you're sure it's eval's fault...

In reply to Re^3: How do I prevent unwanted print output from an eval? by ikegami
in thread How do I prevent unwanted print output from an eval? (RESOLVED! eval NOT THE PROBLEM!) by duggles

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