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authorGravatar Benjamin Barenblat <bbaren@mit.edu>2015-12-23 16:01:51 -0500
committerGravatar Benjamin Barenblat <bbaren@mit.edu>2015-12-23 16:01:51 -0500
commit3d3886672433f0775f772d8d2ee47c5f5e0bc745 (patch)
tree072d171c17d92a6696024256c4b2f5aaa760df35 /src/triple_key_fn.sml
parentbf037ce78c2c76a34ecca0fb8bafa5d5be38968a (diff)
parent4be7962adf740a35222bfd99608c04329a802a04 (diff)
Merge branch 'upstream' into dfsg_clean20151220+dfsg
Diffstat (limited to 'src/triple_key_fn.sml')
-rw-r--r--src/triple_key_fn.sml15
1 files changed, 15 insertions, 0 deletions
diff --git a/src/triple_key_fn.sml b/src/triple_key_fn.sml
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+++ b/src/triple_key_fn.sml
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+functor TripleKeyFn (structure I : ORD_KEY
+ structure J : ORD_KEY
+ structure K : ORD_KEY)
+ : ORD_KEY where type ord_key = I.ord_key * J.ord_key * K.ord_key = struct
+
+type ord_key = I.ord_key * J.ord_key * K.ord_key
+
+fun compare ((i1, j1, k1), (i2, j2, k2)) =
+ case I.compare (i1, i2) of
+ EQUAL => (case J.compare (j1, j2) of
+ EQUAL => K.compare (k1, k2)
+ | ord => ord)
+ | ord => ord
+
+end