Hello

I am fairly new at perl and I am struggling with references. I will post fictitious example underneath of what I would like to do. Hopefully someone can help me.

Intput: textfile with lines likes this:
Obi Wan "tab" Jedi "newline"
Yoda "tab" Jedi "newline"
Count Dooku "tab" Sith "newline"
...

Desired output:
A hash where the affiliations (Jedi of Sith) are the keys and the values are arrays of names (Obi Wan, Yoda, ...)
I want to create the hash while "iterating" over the file line by line.

Problem:
I got stuck with the construction of the hash. First I checked if the key (affiliation) was defined. If not, I added the appropriate key-value pair ($hash{affiliation} => [name])
But I could not find a way to add a name to the anonymous array when the affiliation was already a key.

Many thanks in advance.

In reply to Making a hash of arrays using references by Tmms

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