dragonchild has asked for the wisdom of the Perl Monks concerning the following question:

I've got the following code: 

my @keys = (1 .. 5);
my @values = (6 .. 8);
my %hash;
@hash{@keys} = @values;

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Now, what this does is assign undef to $hash{4} and $hash{5}. Is there a nice way I can do something like: 

@hash{@keys} = @values || '';

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That doesn't work, but that's what I'm trying to do ...

Replies are listed 'Best First'.
Re: Hash slices and too many keys
by merlyn (Sage) on Jul 28, 2001 at 03:31 UTC 
    my @keys = (1..5);
my @values = (6..8);
my %hash;
my @TEMP = @keys; # can use @keys if OK to mangle
@hash{splice @TEMP, 0, @values) = @values;
@hash{@TEMP} = ('') x @TEMP;

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    -- Randal L. Schwartz, Perl hacker

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Re: Hash slices and too many keys (Update cause I can't edit a root node)
by dragonchild (Archbishop) on Jul 27, 2001 at 23:55 UTC
    Update: I got the following to work, but it's really ugly... 

    my @keys = (1 .. 5);
my @values = (6 .. 8);
my %hash;
@hash{@keys} = (@values, ('') x (@columns - @values));

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    There has to be a better way than that ...
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[d/l]

      Well, the straight forward way would be

         foreach( 0 .. $#keys ) {
        $hash{ $keys{ $_ } } = $values{ $_ } || '';
   }

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Re: Hash slices and too many keys
by PrakashK (Pilgrim) on Jul 28, 2001 at 02:57 UTC
    How about: 
    @hash{@keys} = (@values, ('') x @keys);

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    Still ugly, but works.
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Re: Hash slices and too many keys
by mongooser (Initiate) on Jul 28, 2001 at 03:26 UTC
    %hash = map {$_ => shift @values || ''} @keys;

    Sorry, couldn't think of a nice way to do it! :) But it works..
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Re: Hash slices and too many keys
by premchai21 (Curate) on Jul 29, 2001 at 07:37 UTC
    TMTOWTDI: 
    @hash{@keys} = map { ($_ > $#values) ? '' : $values[$_] }
                  (0..$#keys);

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