Beefy Boxes and Bandwidth Generously Provided by pair Networks
laziness, impatience, and hubris
 
PerlMonks  

Re: Checking if hash value exists without implicitly defining it

by trizen (Hermit)
on Feb 14, 2013 at 20:18 UTC ( #1018780=note: print w/ replies, xml ) Need Help??


in reply to Checking if hash value exists without implicitly defining it

Here is a recursive check, without autovivification.

sub _exists { my ($hash, @keys, @exists) = @_; if (exists $hash->{$keys[0]}) { my $key = shift @keys; push @exists, 1, _exists($hash->{$key}, @keys); } return @exists; } sub exists_keys { return &_exists == $#_ ? 1 : (); } my %hash; #$hash{a}{b}{c} = undef; if (exists_keys(\%hash, qw(a b c))) { print "Exists.\n"; } else { print "Doesn't exists.\n"; }


Comment on Re: Checking if hash value exists without implicitly defining it
Download Code

Log In?
Username:
Password:

What's my password?
Create A New User
Node Status?
node history
Node Type: note [id://1018780]
help
Chatterbox?
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others scrutinizing the Monastery: (5)
As of 2015-07-07 01:52 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?

    The top three priorities of my open tasks are (in descending order of likelihood to be worked on) ...









    Results (86 votes), past polls