Mercurial > urweb
annotate src/option_key_fn.sml @ 2305:9083b44bad0a
Short manual note on -sqlcache
author | Adam Chlipala <adam@chlipala.net> |
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date | Sun, 20 Dec 2015 14:20:38 -0500 |
parents | e4a7e3cd6f11 |
children |
rev | line source |
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ziv@2244 | 1 functor OptionKeyFn(K : ORD_KEY) |
ziv@2244 | 2 : ORD_KEY where type ord_key = K.ord_key option = struct |
ziv@2240 | 3 |
ziv@2240 | 4 type ord_key = K.ord_key option |
ziv@2240 | 5 |
ziv@2240 | 6 val compare = |
ziv@2240 | 7 fn (NONE, NONE) => EQUAL |
ziv@2240 | 8 | (NONE, _) => LESS |
ziv@2240 | 9 | (_, NONE) => GREATER |
ziv@2240 | 10 | (SOME x, SOME y) => K.compare (x, y) |
ziv@2240 | 11 |
ziv@2240 | 12 end |