... a) it only wants the keys, and thus is always called in scalar context, ...

Bingo :). If you think about it, what would FIRSTKEY or NEXTKEY return in a list context? There can only be one FIRSTKEY; and only one NEXTKEY at any given point. Each time either of these is called, you should return exactly one key. It is up to you to retain your position internally, and reset that position whenever FIRSTKEY is called.

Examine what is said, not who speaks.
"Efficiency is intelligent laziness." -David Dunham
"Think for yourself!" - Abigail
Timing (and a little luck) are everything!

In reply to Re: (FIRST|NEXT)KEY in context by BrowserUk
in thread (FIRST|NEXT)KEY in context by jweed

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