When you reverse the list you get from a hash, keys and values are exchanged. Making a hash from the reversed list, if two values are the same, only one of the previous keys will survive as a value.

Added - I get 'w2' running your first example, but get the same as you with the second. There may be some optimization with aliases going wrong. I don't see that the construction is supposed to be undefined.

After Compline,
Zaxo

In reply to Re: whats wrong reverse %x = reverse %h? by Zaxo
in thread whats wrong reverse %x = reverse %h? by borisz

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