http://www.perlmonks.org?node_id=125546


in reply to Re: perl -s is evil?
in thread perl -s is evil?

Here's a one liner that exhibits this oddity... 5.6.1 and 5.00503 on linux: 
perl -sle 'print $1' -- -1=foo
foo

/usr/local/bin/perl5.6.1 -sle 'print $1' -- -1=foo
foo

/usr/local/bin/perl5.00503 -sle 'print $1' -- -1=foo
foo

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Can you replicate this?

-Blake

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Re: Re: Re: perl -s is evil?
by buckaduck (Chaplain) on Nov 16, 2001 at 01:56 UTC
    I can replicate that. But more to the point, I also get the following result which is closer to the original post:

    (using both Perl 5.6.0 on Win95 and Perl 5.005_02 on Solaris) 

    % perl -sle '"Hello" =~ /(\w+)/; print $1' -- -1=foo
foo

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    It's just plain wrong. Not only can $1 be assigned to, but afterward it refuses to take the pattern from the regex.

    buckaduck

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      Well, just some fooling around with the last statement Re: Re: Re: perl -s is evil? on my linux box runing Perl 5.005_03, I decided to see what taint checking would do to this example. Wwll here's the results: 
      $ perl -sleT 'use diagnostics; use strict; "Hello" =~ /(\w+)/; print $
+1' -- -1=foo
$

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      While T in any other position returns 
      $ perl -sleT 'use diagnostics; use strict; "Hello" =~ /(\w+)/; print $
+1' -- -1=foo
foo
$

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      Clovs aka jclovs
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        ummm... You've got a bit of a command like goof there.... The following one-liner illustrates it. Can you figure it out? 
        perl -weT 'print "I like jellybeans"'
Useless use of a constant in void context at -e line 1.

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        consult perlrun for hints. ;-)

        -Blake

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