Keys of a hash are always unique,

You're right of course.

I was thinking about an iterator which would need to check whether a value had been seen before but ...

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re^4: Non-Repetitive Random Numbers by BrowserUk
in thread Non-Repetitive Random Numbers by Anonymous Monk

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