diff options
author | Adam Chlipala <adamc@hcoop.net> | 2009-08-09 16:13:27 -0400 |
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committer | Adam Chlipala <adamc@hcoop.net> | 2009-08-09 16:13:27 -0400 |
commit | 1f98468265e6f5d652ed107a0bd89a319eca0297 (patch) | |
tree | 007835aa119d7ec7cae1d7de078850147ab9ca13 /lib/ur/monad.ur | |
parent | f223822addd309cd20b5b01e34548496e6d33251 (diff) |
Library improvements; proper list [un]urlification; remove server-side ServerCalls; eta reduction in type inference
Diffstat (limited to 'lib/ur/monad.ur')
-rw-r--r-- | lib/ur/monad.ur | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/lib/ur/monad.ur b/lib/ur/monad.ur index 73001094..356173fd 100644 --- a/lib/ur/monad.ur +++ b/lib/ur/monad.ur @@ -7,3 +7,38 @@ fun exec [m ::: Type -> Type] (_ : monad m) [ts ::: {Type}] r (fd : folder ts) = (return {}) [ts] fd r fun ignore [m ::: Type -> Type] (_ : monad m) [t] (v : m t) = x <- v; return () + +fun foldR [K] [m] (_ : monad m) [tf :: K -> Type] [tr :: {K} -> Type] + (f : nm :: Name -> t :: K -> rest :: {K} + -> [[nm] ~ rest] => + tf t -> tr rest -> m (tr ([nm = t] ++ rest))) + (i : tr []) [r :: {K}] (fl : folder r) = + Top.fold [fn r :: {K} => $(map tf r) -> m (tr r)] + (fn [nm :: Name] [t :: K] [rest :: {K}] [[nm] ~ rest] + (acc : _ -> m (tr rest)) r => + acc' <- acc (r -- nm); + f [nm] [t] [rest] ! r.nm acc') + (fn _ => return i) + [_] fl + +fun foldR2 [K] [m] (_ : monad m) [tf1 :: K -> Type] [tf2 :: K -> Type] [tr :: {K} -> Type] + (f : nm :: Name -> t :: K -> rest :: {K} + -> [[nm] ~ rest] => + tf1 t -> tf2 t -> tr rest -> m (tr ([nm = t] ++ rest))) + (i : tr []) [r :: {K}] (fl : folder r) = + Top.fold [fn r :: {K} => $(map tf1 r) -> $(map tf2 r) -> m (tr r)] + (fn [nm :: Name] [t :: K] [rest :: {K}] [[nm] ~ rest] + (acc : _ -> _ -> m (tr rest)) r1 r2 => + acc' <- acc (r1 -- nm) (r2 -- nm); + f [nm] [t] [rest] ! r1.nm r2.nm acc') + (fn _ _ => return i) + [_] fl + +fun mapR [K] [m] (_ : monad m) [tf :: K -> Type] [tr :: K -> Type] + (f : nm :: Name -> t :: K -> tf t -> m (tr t)) = + @@foldR [m] _ [tf] [fn r => $(map tr r)] + (fn [nm :: Name] [t :: K] [rest :: {K}] [[nm] ~ rest] (v : tf t) + (acc : $(map tr rest)) => + v' <- f [nm] [t] v; + return (acc ++ {nm = v'})) + {} |