Re^2: initialize all values in a hash

"You could do it with a tied hash, but I can't find a module that does this on CPAN, so you'd need to do it yourself."

OK, I've just gone and uploaded Hash::DefaultValue to CPAN. Usage:

tie my %hash, 'Hash::DefaultValue', 60;
$hash{foo} = 8;
say $hash{foo};   # says 8
say $hash{bar};   # says 60
[download]

perl -E'sub Monkey::do{say$_,for@_,do{($monkey=[caller(0)]->[3])=~s{::}{ }and$monkey}}"Monkey say"->Monkey::do'

Comment on Re^2: initialize all values in a hash Download Code

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Re^3: initialize all values in a hash by DrHyde (Prior) on May 18, 2012 at 14:03 UTC
See also Tie::Hash::Vivify :-)	[reply]
Re^4: initialize all values in a hash by tobyink (Canon) on May 18, 2012 at 14:27 UTC
Oh, that's annoying. In fairness, a documented feature of mine is that it explicitly avoids autovivifying keys. So with Tie::Hash::Vivify, this is true: `tie my %hash, 'Tie::Hash::Vivify', sub { 10 }; say $hash{foo}; # says 10 my $is_this_true = exists $hash{foo};` [download] Whereas this is false: `tie my %hash, 'Hash::DefaultValue', sub { 10 }; say $hash{foo}; my $is_this_true = exists $hash{foo};` [download] Another feature of Hash::DefaultValue is that the coderef gets passed a copy of the key, so can use that information when generating the default value. `tie my %hash, 'Hash::DefaultValue', sub { uc }; say $hash{foo}; # says "FOO"` [download] `perl -E'sub Monkey::do{say$_,for@_,do{($monkey=[caller(0)]->[3])=~s{::}{ }and$monkey}}"Monkey say"->Monkey::do'`	[reply] [d/l] [select]
Re^5: initialize all values in a hash by DrHyde (Prior) on May 18, 2012 at 15:35 UTC
I mostly use Tie::Hash::Vivify to prevent autovivification thus: `my $hashref = Tie::Hash::Vivify->new( sub { confess("No auto-vivifying!\n".Dumper(\@_)) } )` [download] to avoid those annoyingly hard-to-track-down bugs where you've typoed a hash key.	[reply] [d/l]
Re^6: initialize all values in a hash by tobyink (Canon) on May 18, 2012 at 16:49 UTC