in reply to Re: get a certain number of words from a line
in thread get a certain number of words from a line

You seem to be under the impression that 
\(0..10)

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is the same as 
[0..10]

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Update: It appears that they are the same for this particular case, which is (IMO) a Bad Idea, since the \() construct is already a not-uncommon source of confusion. Why was it considered important to make \(something) behave like [something] iff something is a range?
We're not really tightening our belts, it just feels that way because we're getting fatter.

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Re^3: get a certain number of words from a line
by sleepingsquirrel (Chaplain) on Jun 15, 2004 at 18:26 UTC
    I'm under the impression that \(0..10) is a reference to an 11 item list (0,1,2,3,4,5,6,7,8,9,10). And further more, I'm under the impression that... 
    $ref=\(1..10);
@a[@$ref];

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    ...is an eleven item array slide of @a, which happens to be equivalent to @a[0..10]. Try it, you might like it ;)
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      I'd like to try it, but I don't have perl5 where I am this week. My understanding is that \(1..10) is shorthand for (\1,\2,\3,...,\10), and that your list will be flattened, so that (\(1..10),\(11..15)) is the same as \(1..15).

      It's not a feature I've used, myself, so I could certainly be misunderstanding it. If I am, I would genuinely appreciate someone making it clear to me.

      It took me a minute to decode "array slide" as "array slice". I thought you were talking about a feature I'd never heard of!

      Update: from perlref: 

      Taking a reference to an enumerated list is not the same as using squa
+re brackets--instead it's the same as creating a list of references!

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      We're not really tightening our belts, it just feels that way because we're getting fatter.
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        Hmmm... Apparently not for my perl... 
        greg@sparky:~/test$ cat ./list_ref 
#!/usr/bin/perl -w

@a=qw/zero one two three four five/;
$ref=\(1..3);
@b=@a[@$ref];

print "\n \@a=@a\n \$ref=$ref\n \@b=@b\n\n";

greg@sparky:~/test$ ./list_ref 

 @a=zero one two three four five
 $ref=ARRAY(0x813dcc0)
 @b=one two three

greg@sparky:~/test$ perl -v

This is perl, v5.8.0 built for i486-linux

Copyright 1987-2002, Larry Wall

Perl may be copied only under the terms of either the Artistic License
+ or the
GNU General Public License, which may be found in the Perl 5 source ki
+t. <snip>

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        ...And sorry for the typo. This thread (among others) has finally inspired me to create my first perlmonks .sig.

        -- All code is 100% tested and functional unless otherwise noted.
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        "Enumerated list" must be the key concept. 
        greg@sparky:~/test$ cat enum 
#!/usr/bin/perl -w
use Data::Dumper;

$ref=\(0..3);
$enum_list=\(4,5,6);

print "\n".Dumper($ref)."\n";
print "\n".Dumper($enum_list)."\n";

greg@sparky:~/test$ ./enum 

$VAR1 = [
          0,
          1,
          2,
          3
        ];


$VAR1 = \6;

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        -- All code is 100% tested and functional unless otherwise noted.
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