Re: Hash multiple initialization

New hash:

my %hash = (
   ( map { $_=>'toto' } qw( a b c f t u ) ),
   ( map { $_=>'titi' } qw( b g k p ) ),
);
[download]

Existing hash:

$hash{$_} = 'toto' for qw( a b c f t u );
$hash{$_} = 'titi' for qw( b g k p );
[download]

You have "b" twice, which means one (the earlier one) will get erased.

Comment on Re: Hash multiple initialization Select or Download Code

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Re^2: Hash multiple initialization by AnomalousMonk (Archbishop) on Oct 08, 2008 at 20:13 UTC
Might this be a case in which prototyping is actually useful as a syntactic sweetener? `sub mass_init (\%\@$); my @init_to_toto = qw{ a b c f t u }; my %hash = ( y => 'pre', z => 'pre', ); mass_init(%hash, @init_to_toto, 'toto'); mass_init(%hash, @{[ qw(b g k p) ]}, 'TITI'); use Data::Dumper; print Dumper \%hash; sub mass_init (\%\@$) { my ($hashref, $arrayref, $string) = @_; # $hashref->{$_} = $string for @$arrayref; @{ %$hashref }{ @$arrayref } = ($string) x @$arrayref; }` [download] Output: `$VAR1 = { 'a' => 'toto', 'y' => 'pre', 'p' => 'TITI', 'c' => 'toto', 'u' => 'toto', 'k' => 'TITI', 'g' => 'TITI', 'b' => 'TITI', 'z' => 'pre', 'f' => 'toto', 't' => 'toto' };` [download]	[reply] [d/l] [select]
Re^3: Hash multiple initialization by ikegami (Patriarch) on Oct 09, 2008 at 01:13 UTC
I don't see the point of the prototype. It actually makes your example caller bigger! `my @init_to_toto = qw{ a b c f t u }; my %hash = ( y => 'pre', z => 'pre', ); mass_init(\%hash, \@init_to_toto, 'toto'); mass_init(\%hash, [qw( b g k p )], 'TITI'); use Data::Dumper; print Dumper \%hash; sub mass_init { my ($hashref, $arrayref, $string) = @_; # $hashref->{$_} = $string for @$arrayref; @{ %$hashref }{ @$arrayref } = ($string) x @$arrayref; }` [download]	[reply] [d/l]