in reply to Re: Opinion: where Perl5 wasn't attractive for me
in thread Opinion: where Perl5 wasn't attractive for me

I don't know if it is trolling? (Yesterday I read some articles about popularity of Perl and tried to remember which things in Perl took away some of my time and mood; And I think that they could be annoying for other beginners.)

Why did I used $hash{length}? It's because I used $array[length] many times. And usually I suppose (cargo-cult?) that similar construct should behave similar. And I have used $hash{1+1} before, and haven't gained "('1+1' => smth)". So I dislike that bareword exception that you mean.
$_="abc";
$h{1+3}=41;
$h{a+3}=42;
$h{- length}=43;
$h[1+3]=41;
$h[a+3]=42;
$h[- length]=43;
$h[length]=44;
$,='|';
print %h,"\n",@h
__END__
-length|43|4|41|3|42|
|||43|44|41

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Re^3: Opinion: where Perl5 wasn't attractive for me
by SuicideJunkie (Vicar) on Nov 19, 2014 at 14:59 UTC

    I can't imagine many cases at all where you might want to use length $_ as an index or key, but almost every case where you would want to be able to type a key without having quotes all over the place.

    The simplest way to do what you want is with a leading unary + to make it not be a bareword.

    use strict;
use warnings;
use Data::Dumper;
my %foo;
$foo{+length} = 42;
$foo{length} = 'interminable';
print Dumper \%foo;

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    Gives: 
    Use of uninitialized value $_ in hash element at test.pl line 5.
$VAR1 = {
          '' => 42,
          'length' => 'interminable'
        };

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      Ok. Thats true. And I used $hash{(length)}++ to save occurences of the substring lengths.
      And this works too: $foo{- -length} = 42;, but '+' of course is better.
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