Is it possible to determine the number of values for a particular hash key?

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

How can I determine the number of values for a particular key in a hash? For example:


my %HoA;

for my $key ( keys %HoA ) {
        // gives me the correct first value in this key
        my $value = $HoA{$key}[0];
        // does not give me the correct number of values in this key
        my $size = length($HoA{$key});
}
[download]

Comment on Is it possible to determine the number of values for a particular hash key? Download Code

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Re: Is it possible to determine the number of values for a particular hash key? by state-o-dis-array (Hermit) on Oct 24, 2013 at 15:03 UTC
`my $size = @{$HoA{$key}};` [download]	[reply] [d/l]
Re^2: Is it possible to determine the number of values for a particular hash key? by SuzuBell (Acolyte) on Oct 24, 2013 at 15:46 UTC
Thank you.	[reply]
Re: Is it possible to determine the number of values for a particular hash key? by toolic (Bishop) on Oct 24, 2013 at 15:08 UTC
length `perldoc -f length` [download] This function cannot be used on an entire array or hash to find out how many elements these have. For that, use "scalar @array" and "scalar keys %hash", respectively.	[reply] [d/l]
Re: Is it possible to determine the number of values for a particular hash key? by pajout (Curate) on Oct 25, 2013 at 09:20 UTC
Strictly spoken, number of values for a particular key in a hash is 0 or 1. Of course, if the value is reference to array, that array could have many values.	[reply]


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