Posted by Erik Stel on Jul 01, 2017; 7:41am
URL: https://forum.world.st/Validate-password-with-PBKDF2-tp4952973p4953168.html

Hi Francis,

You write:

Pharo Smalltalk Users mailing list wrote

FIY

UUID new asByteArray

does not give a ByteArray because UUID is a subclass of ByteArray and
asByteArray returns self

(Entering teacher mode)
This actually means that "UUID new asByteArray" does answer a ByteArray. It will answer (as you mentioned correctly) itself. Since a UUID is a ByteArray it means it will answer a ByteArray (in contrary to your statement).

To put it differently: The inheritance relation (UUID being a subclass of ByteArray) is a "IS-A" relation. So any UUID is a ByteArray.

This means however the message "asByteArray" did not have to be send of course (it is already a ByteArray). I was not sure the class UUID was actually a subclass of ByteArray when writing my reply. Turns out it is.

Cheers,
Erik