Re: [Feature Request] "first:" "last:" sections in a "foreach" block

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From: Jon Skeet [C# MVP] (skeet_at_pobox.com)
Date: 04/05/04 

Date: Mon, 5 Apr 2004 20:09:31 +0100

Dilip Krishnan <dilipdotnet..NOSPAM..@apdiya.com> wrote:
> I would think that by the definition of foreach, the language construct
> is unable to predict the size of the enumerable in question. Which would
> mean that the foreach loop would need to read-ahead to determine the
> ordinality of the enumerable list. IMHO that would make the whole
> foreach inefficient would'nt you say?

You don't need to know the ordinality though - you only need to know
first or last. First is obvious, and the "last" bit you just execute
when the next MoveNext returns false (or whatever - I can't remember
the exact interface offhand). It would be slightly trickier to make the
"last" case not also execute "other", and it would be easier to
basically make that something executed *as well as* the "other" case,
but other than that it's not tricky. 

-- 
Jon Skeet - <skeet@pobox.com>
http://www.pobox.com/~skeet
If replying to the group, please do not mail me too

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