What constitutes a "first-class object" tends to vary by language. Strictly speaking in generic inter-language terminology, arrays and hashes in Perl are not first-class objects by many definitions. One cannot pass a hash or array into a function intact. One cannot return a hash or an array from a function, or assign one hash or array directly to another. Without library support (DBM::Deep or such) the values are what gets copied (with a hash key being a special type of "value" that is the key to another value).

The only first-class objects in a very strict sense of which I can think right now in Perl are scalars, references, typeglobs, and perhaps (classic, blessed reference to something) object instances. I hesitate to include object instances since they are "just blessed references", but when returned or assigned they do carry their class information and instance information with them at the language level.

In reply to Re^13: If you believe in Lists in Scalar Context, Clap your Hands by mr_mischief
in thread If you believe in Lists in Scalar Context, Clap your Hands by gone2015

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