in reply to Re^2: get a certain number of words from a line
in thread get a certain number of words from a line

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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Re^4: get a certain number of words from a line
by Roy Johnson (Monsignor) on Jun 15, 2004 at 19:10 UTC
    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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[d/l]
        What do you get if you do 
        $x = \((0..3));

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        ?

        As a general rule, I would recommend use of [0..10] instead of the capricious \(0..10), since the former is always a way to get an array ref (and is a char shorter), while the latter is usually a way to make a list of references.

        We're not really tightening our belts, it just feels that way because we're getting fatter.
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