Okay, I didn't duplicate exactly what you said. The following code: 
#!/usr/bin/env perl      

use strict;

my $s = 'eabcde';
my $t = $s;

print "$t\n";
$t =~ tr/abcd/efgh/;
print "$t\n";

print '*' x 4, $/;

my $search = 'abcd';
my $replace = 'efgh';

$t = $s;
print "$t\n";

eval "\$t =~ tr/$search/$replace/";

print "$search\n";
print "$replace\n";
print "$t\n";

[download]
...does give me the expected results: 
eabcde
eefghe
****
eabcde
abcd
efgh
eefghe

[download]
Why the difference?

In reply to Re^3: doing tr/// on-the-fly? by Anonymous Monk
in thread doing tr/// on-the-fly? by Anonymous Monk

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