in reply to ::'s role in strings

It means you can do the following: 

>perl -e "$a = Class::; print $a"
Class

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It even works under strict, and it's doesn't issue any warnings if the package exists.

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Re^2: ::'s role in strings
by eff_i_g (Curate) on Apr 27, 2006 at 18:56 UTC
    Here is what I tried on my machine: 
    > perl -v

This is perl, v5.8.6 built for PA-RISC2.0

Copyright 1987-2004, Larry Wall

...

> perl -e "$a = Class::; print $a"
a: Undefined variable.

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    I guess my follow up question is: Why does/should this work?
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      I used 5.6.1.

      a: Undefined variable.

      I'm susprised by the output you get. Is that really what you got for output? from perl? No, it's from your shell. Use single quotes.

      Why does/should this work?

      It's probably just an unintentional side-effect. It's to avoid ambiguitities when using indirect method calls. I wouldn't use :: as a quoting mechanism.

      Updated: Thanks to japhy and jhourcle for the corrections/elaborations.

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        It works so that you can write: 
        use Foo;  # defines Foo::new() among others
sub Foo { "Oh no, Mr. Bill!" }
$x = new Foo::;

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        because $x = new Foo would NOT work under those circumstances.
        Jeff japhy Pinyan, P.L., P.M., P.O.D, X.S.: Perl, regex, and perl hacker
        How can we ever be the sold short or the cheated, we who for every service have long ago been overpaid? ~~ Meister Eckhart
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        Oops. The shell problem should have been obvious--sorry about that. Thanks for clearing this up everyone.
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        I'm not surprised at all. Double quoted strings are bad in some shells, as '$a' might be processed by the shell, not by perl, therefore, might result in a shell error.

        $ perl -v

This is perl, v5.8.6 built for darwin-thread-multi-2level
(with 2 registered patches, see perl -V for more detail)

...

$ perl -e "$a = Class::; print $a"
syntax error at -e line 1, near "="
Execution of -e aborted due to compilation errors.
$ perl -e '$a = Class::; print $a'
Class

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        Update: inserted word 'some'

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[d/l]

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