Mercurial > urweb
changeset 1736:7ec8dab190a7
Better discovery of type class instances from recursive definitions
author | Adam Chlipala <adam@chlipala.net> |
---|---|
date | Wed, 02 May 2012 08:34:50 -0400 |
parents | ec47f49c6aa3 |
children | 78d7cc9c9b18 |
files | src/elaborate.sml tests/newMessage.ur |
diffstat | 2 files changed, 19 insertions(+), 1 deletions(-) [+] |
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--- a/src/elaborate.sml Wed May 02 08:23:30 2012 -0400 +++ b/src/elaborate.sml Wed May 02 08:34:50 2012 -0400 @@ -3912,8 +3912,11 @@ expError env (IllegalRec (x, e')); ((x, n, c', e'), gs1 @ gs) end) gs vis + + val vis = map (fn (x, n, t, e) => (x, n, normClassConstraint env t, e)) vis + val d = (L'.DValRec vis, loc) in - ([(L'.DValRec vis, loc)], (env, denv, gs)) + ([d], (E.declBinds env d, denv, gs)) end | L.DSgn (x, sgn) =>
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/tests/newMessage.ur Wed May 02 08:34:50 2012 -0400 @@ -0,0 +1,15 @@ +datatype message = NewQuestion of { Id : string} + | Something of {Blah : int} + +fun showMessage (message : message) = + case message of + NewQuestion {Id = a} => a + | Something {Blah = x} => "blah" + +val show_mes = mkShow showMessage + +fun showTwoTuple [a] [b] (_ : show a) (_: show b) = mkShow (fn (two_tuple : {1:a, 2:b}) => + "(" ^ show two_tuple.1 ^ ", " ^ show two_tuple.2 ^ ")" + + ) +val om = show (Something {Blah = 1}, Something {Blah = 2})