diff options
| author |  Adam Chlipala <adam@chlipala.net> | 2015-11-01 17:02:16 -0500 |
|---|---|---|
| committer | Adam Chlipala <adam@chlipala.net> | 2015-11-01 17:02:16 -0500 |
| commit | dc8c8ed99b79e4f3c3c38f131dd7563148524591 (patch) | |
| tree | 6fc5bda32c27ba5f8bca4712c5fe95b743dbe798 | |
| parent | c0670f7c2517948966a5c037b401304a67bb85c6 (diff) | |
Change behavior of SQL equality to do the intuitive thing for nullable types
| -rw-r--r-- | lib/ur/basis.urs | 3 | ||||
| -rw-r--r-- | src/monoize.sml | 39 |
2 files changed, 34 insertions, 8 deletions
diff --git a/lib/ur/basis.urs b/lib/ur/basis.urs index e4eaa0a9..a4872c32 100644 --- a/lib/ur/basis.urs +++ b/lib/ur/basis.urs @@ -554,6 +554,9 @@ val sql_div : t ::: Type -> sql_arith t -> sql_binary t t t val sql_mod : sql_binary int int int val sql_eq : t ::: Type -> sql_binary t t bool +(* Note that the semantics of this operator on nullable types are different than for standard SQL! + * Instead, we do it the sane way, where [NULL = NULL]. *) + val sql_ne : t ::: Type -> sql_binary t t bool val sql_lt : t ::: Type -> sql_binary t t bool val sql_le : t ::: Type -> sql_binary t t bool diff --git a/src/monoize.sml b/src/monoize.sml index 8934db2c..dd2c41c5 100644 --- a/src/monoize.sml +++ b/src/monoize.sml @@ -2592,22 +2592,45 @@ fun monoExp (env, st, fm) (all as (e, loc)) = _), _), _), _), _), _), - _), _), + arg1), _), _), _), _) => let val s = (L'.TFfi ("Basis", "string"), loc) + + val default = strcat [str "(", + (L'.ERel 1, loc), + str " ", + (L'.ERel 2, loc), + str " ", + (L'.ERel 0, loc), + str ")"] + + val body = case #1 arg1 of + L.CApp ((L.CFfi ("Basis", "option"), _), _) => + (L'.ECase ((L'.ERel 2, loc), + [((L'.PPrim (Prim.String (Prim.Normal, "=")), loc), + strcat [str "((", + (L'.ERel 1, loc), + str " ", + (L'.ERel 2, loc), + str " ", + (L'.ERel 0, loc), + str ") OR ((", + (L'.ERel 1, loc), + str ") IS NULL AND (", + (L'.ERel 0, loc), + str ") IS NULL))"]), + ((L'.PWild, loc), + default)], + {disc = s, + result = s}), loc) + | _ => default in ((L'.EAbs ("c", s, (L'.TFun (s, (L'.TFun (s, s), loc)), loc), (L'.EAbs ("e1", s, (L'.TFun (s, s), loc), (L'.EAbs ("e2", s, s, - strcat [str "(", - (L'.ERel 1, loc), - str " ", - (L'.ERel 2, loc), - str " ", - (L'.ERel 0, loc), - str ")"]), loc)), loc)), loc), + body), loc)), loc)), loc), fm) end | L.EFfi ("Basis", "sql_and") => (str "AND", fm) |