diff options
| author |  Karn Kallio <kkallio@eka> | 2011-07-06 17:54:23 -0530 |
|---|---|---|
| committer | Karn Kallio <kkallio@eka> | 2011-07-06 17:54:23 -0530 |
| commit | f94091da4205dc783cb4d452b935c3f20284278d (patch) | |
| tree | 05f43354a940adfb7fb7ecb8300920d7e7fa604a | |
| parent | ab9282b7359aa50b6c2f094e3cd8571ffa2dc3ac (diff) | |
Narrow Maybe match case.
| -rw-r--r-- | src/mono_reduce.sml | 13 |
1 files changed, 5 insertions, 8 deletions
diff --git a/src/mono_reduce.sml b/src/mono_reduce.sml index 06075954..3507480e 100644 --- a/src/mono_reduce.sml +++ b/src/mono_reduce.sml @@ -204,15 +204,12 @@ fun match (env, p : pat, e : exp) = else No - | (PCon (_, PConVar n1, NONE), ECon (_, PConVar n2, NONE)) => + | (PCon (_, PConVar n1, po), ECon (_, PConVar n2, eo)) => if n1 = n2 then - Yes env - else - No - - | (PCon (_, PConVar n1, SOME p), ECon (_, PConVar n2, SOME e)) => - if n1 = n2 then - match (env, p, e) + case (po, eo) of + (NONE, NONE) => Yes env + | (SOME p, SOME e) => match (env, p, e) + | _ => Maybe else No |