Re: Hash keys reference

You can't refer to $hash{key} until it exists, and it doesn't exist until that hash creation is done. You'll need to do it separately.

However, you can do something bizarre like this:

my @foo;
@foo[0..2] = (10, \$foo[0], 20);
print ${ $foo[1] };  # 10
[download]

That works, while

my @foo;
@foo = (10, \$foo[0], 20);
print ${ $foo[1] };  # nothing
[download]

does not. ;)

_____________________________________________________
Jeff[japhy]Pinyan: Perl, regex, and perl hacker, who'd like a (from-home) job
s++=END;++y(;-P)}y js++=;shajsj<++y(p-q)}?print:??;

Comment on Re: Hash keys reference Select or Download Code

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•Re: Re: Hash keys reference by merlyn (Sage) on Mar 04, 2002 at 03:22 UTC
Well, actually, the reference makes it exist. It's the hash assignment that delinks it. Witness the result of: `%last_name = (); $x = \$last_name{fred}; # creates hash element, value is undef $last_name{fred} = "flintstone"; print $$x; # prints flintstone` [download] So, your array-slice example would also work on a hash slice: `undef %last_name; @last_name{qw(fredref fred)} = (\$last_name{fred}, " +flintstone");` [download] -- Randal L. Schwartz, Perl hacker	[reply] [d/l] [select]
Re: •Re: Re: Hash keys reference by japhy (Canon) on Mar 04, 2002 at 03:30 UTC
Yes, I'm fully aware of that, which is why I used the example. `;)` _____________________________________________________ Jeff`[japhy]`Pinyan: Perl, regex, and perl hacker, who'd like a (from-home) job `s++=END;++y(;-P)}y js++=;shajsj<++y(p-q)}?print:??;`	[reply]