[pm-h] when is a anonymous hash reference is not...

[G. Wade Johnson]

Good catch and worth reminding people.

Perl usually does the right thing. But in that specific case, the
syntax could be either a naked block or a hash and Perl guessed wrong.

An alternative would be

sub c {+{@list}}

The '+' would only be syntactically valid before a scalar,
disambiguating the syntax.

G. Wade

On Mon, 20 Apr 2015 13:34:05 +0000 (UTC)
"Michael R. Davis via Houston" <houston at pm.org> wrote:

> Perl Folks,Here's an interesting Perl-ism that bit me yesterday.
> I've been starting to drop my sub "return" but I'm going back to
> being explicit as the performance hit has been fixed in later Perls
> and it just doesn't pay for itself in debugging.  Moral of the story:
> be explicit. I hope someone finds this helpful.Mike  perl -e ' use
> strict; use warnings; use Data::Dumper qw{Dumper}; our @list=(a=>1,
> b=>2); sub a {{a=>1, b=>2}};   #{} is anon hash ref sub b
> {[@list]};        #{} is anon array ref sub c {{@list}};        #{}
> is block returns list sub d {return {@list}}; #{} is anon hash
> refprint Dumper({a=>a(), b=>b(), c=>c(), d=>d()}); '
> Odd number of elements in anonymous hash at -e line 11.
> $VAR1 = {
>           '1' => 'b',
>           'c' => 'a',
>           'a' => {
>                    'a' => 1,
>                    'b' => 2
>                  },
>           'b' => [
>                    'a',
>                    1,
>                    'b',
>                    2
>                  ],
>           'HASH(0x10b8b70)' => undef,
>           '2' => 'd'
>         };
>  


-- 
You forgot the first rule of the fanatic: when you become obsessed with
the enemy, you become the enemy.     -- Jeffrey Sinclair in "Infection"