Software / code / prosody
Changeset
1659:6092fc9b078b
util.iterators: Add head() iterator, to return the first n items
| author | Matthew Wild <mwild1@gmail.com> |
|---|---|
| date | Mon, 10 Aug 2009 15:07:32 +0100 |
| parents | 1658:0baa849761b6 |
| children | 1660:ae2f60a20428 |
| files | util/iterators.lua |
| diffstat | 1 files changed, 12 insertions(+), 0 deletions(-) [+] |
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--- a/util/iterators.lua Mon Aug 10 14:29:28 2009 +0100 +++ b/util/iterators.lua Mon Aug 10 15:07:32 2009 +0100 @@ -78,6 +78,18 @@ return x; end +-- Return the first n items an iterator returns +function head(n, f, s, var) + local c = 0; + return function (s, var) + if c >= n then + return nil; + end + c = c + 1; + return f(s, var); + end, s; +end + -- Convert the values returned by an iterator to an array function it2array(f, s, var) local t, var = {};
