I have a behavior that is even more difficult to understand (running Perl 5.14.4).

Running the test directly under the Perl debugger: 

  DB<1> $x = "a\n";

  DB<2> $x = chomp $x;

  DB<3> print $x
1

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And running the same at the command line: 
$ perl -E 'my $x = "a\n";  $x = chomp $x; say $x'
0

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So I get 1 under the debugger et 0 at the command line. Isn't it strange?

And, BTW, using another variable solves the issue: 

$  perl -E 'my $x = "a\n"; my $y = chomp $x; say $y;'
1

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This leads me to believe that doing this: 
$x = chomp $x;

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might well be undefined behavior (and should most probably be avoided), just as: 
$c = ++$c;

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is undefined both in C and in Perl. (And different C compilers actually give different results on the code above, I have tried it once in the past.)

In reply to Re: Assigning the result of a chomp to the chomped var itself. by Laurent_R
in thread Assigning the result of a chomp to the chomped var itself. by choroba

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