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selecting values from hash via list

by leocharre (Priest)
on Nov 06, 2009 at 21:01 UTC ( #805582=perlquestion: print w/replies, xml ) Need Help??
leocharre has asked for the wisdom of the Perl Monks concerning the following question:

I have a hash or hashref. Let's make it easy, a hash.
my %h = ( name => 'dumdum', age => 14, zone => 'a4', pocket => 'empty', );
I'm going to print some of this data with printf..
printf "%-20s %5d %s\n", $h{name}, $h{age}, $h{zone};

What's another way to specify those three values? Specifically, as you would as list args.. I know this has to be out there.

I like this trick to init hash keys (learned it here)..

my %a; my @a = qw/name age zone pocket/; @a{@a}=(); # looks weird, eh? ;-) # now 'exists $a{name}' is true!
Maybe there's some way to ...err... uhhhm ...
printf "%-20s %5d %s\n", @h{qw/name age zone/};

(sorry about the title, dunno how else the heck to word this)


Silly me, that second example, that was the solution, thanks toolic

Replies are listed 'Best First'.
Re: selecting values from hash via list (slice)
by toolic (Bishop) on Nov 06, 2009 at 21:14 UTC
    I'm confused. Your 2 printf statements print the same thing for me. Isn't that what you want -- to use a hash slice to save typing? See Slices.
    printf "%-20s %5d %s\n", $h{name}, $h{age}, $h{zone}; printf "%-20s %5d %s\n", @h{qw/name age zone/};
      Oh.. dear... it works.. I thought I was making up code!

      I thought this was nonsense! : printf "%-20s %5d %s\n", @h{qw/name age zone/};

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