Ah, ok. I see now. The book reads: "Here's how you might write a function that does a kind of set intersection by returning a list of keys occurring in all the hashes passed to it..."

The part that says "by returning a list of keys occurring in all the hashes passed to it..." led me to think "intersection" meant "union". It's been a while since I've had set theory. Still, "returning a list of keys common to each of the hashes passed to it" would be a lot less ambiguous.

Thanks!

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In reply to Re: Re: Code mistake in Camel book? by nysus
in thread Code mistake in Camel book? by nysus

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