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annotate lib/ur/monad.ur @ 955:01a4d936395a

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tail example working
author Adam Chlipala <adamc@hcoop.net>
date Thu, 17 Sep 2009 17:11:23 -0400
parents 37dd42935dad
children 8d3aa6c7cee0
rev   line source
adamc@834 1 fun exec [m ::: Type -> Type] (_ : monad m) [ts ::: {Type}] r (fd : folder ts) =
adamc@834 2 foldR [m] [fn ts => m $ts]
adamc@834 3 (fn [nm :: Name] [v :: Type] [rest :: {Type}] [[nm] ~ rest] action acc =>
adamc@834 4 this <- action;
adamc@834 5 others <- acc;
adamc@834 6 return ({nm = this} ++ others))
adamc@834 7 (return {}) [ts] fd r
adamc@898 8
adamc@898 9 fun ignore [m ::: Type -> Type] (_ : monad m) [t] (v : m t) = x <- v; return ()
adamc@905 10
adamc@917 11 fun mp [m] (_ : monad m) [a] [b] f m =
adamc@917 12 v <- m;
adamc@917 13 return (f v)
adamc@917 14
adamc@905 15 fun foldR [K] [m] (_ : monad m) [tf :: K -> Type] [tr :: {K} -> Type]
adamc@905 16 (f : nm :: Name -> t :: K -> rest :: {K}
adamc@905 17 -> [[nm] ~ rest] =>
adamc@905 18 tf t -> tr rest -> m (tr ([nm = t] ++ rest)))
adamc@905 19 (i : tr []) [r :: {K}] (fl : folder r) =
adamc@905 20 Top.fold [fn r :: {K} => $(map tf r) -> m (tr r)]
adamc@905 21 (fn [nm :: Name] [t :: K] [rest :: {K}] [[nm] ~ rest]
adamc@905 22 (acc : _ -> m (tr rest)) r =>
adamc@905 23 acc' <- acc (r -- nm);
adamc@905 24 f [nm] [t] [rest] ! r.nm acc')
adamc@905 25 (fn _ => return i)
adamc@905 26 [_] fl
adamc@905 27
adamc@905 28 fun foldR2 [K] [m] (_ : monad m) [tf1 :: K -> Type] [tf2 :: K -> Type] [tr :: {K} -> Type]
adamc@905 29 (f : nm :: Name -> t :: K -> rest :: {K}
adamc@905 30 -> [[nm] ~ rest] =>
adamc@905 31 tf1 t -> tf2 t -> tr rest -> m (tr ([nm = t] ++ rest)))
adamc@905 32 (i : tr []) [r :: {K}] (fl : folder r) =
adamc@905 33 Top.fold [fn r :: {K} => $(map tf1 r) -> $(map tf2 r) -> m (tr r)]
adamc@905 34 (fn [nm :: Name] [t :: K] [rest :: {K}] [[nm] ~ rest]
adamc@905 35 (acc : _ -> _ -> m (tr rest)) r1 r2 =>
adamc@905 36 acc' <- acc (r1 -- nm) (r2 -- nm);
adamc@905 37 f [nm] [t] [rest] ! r1.nm r2.nm acc')
adamc@905 38 (fn _ _ => return i)
adamc@905 39 [_] fl
adamc@905 40
adamc@910 41 fun foldR3 [K] [m] (_ : monad m) [tf1 :: K -> Type] [tf2 :: K -> Type] [tf3 :: K -> Type] [tr :: {K} -> Type]
adamc@910 42 (f : nm :: Name -> t :: K -> rest :: {K}
adamc@910 43 -> [[nm] ~ rest] =>
adamc@910 44 tf1 t -> tf2 t -> tf3 t -> tr rest -> m (tr ([nm = t] ++ rest)))
adamc@910 45 (i : tr []) [r :: {K}] (fl : folder r) =
adamc@910 46 Top.fold [fn r :: {K} => $(map tf1 r) -> $(map tf2 r) -> $(map tf3 r) -> m (tr r)]
adamc@910 47 (fn [nm :: Name] [t :: K] [rest :: {K}] [[nm] ~ rest]
adamc@910 48 (acc : _ -> _ -> _ -> m (tr rest)) r1 r2 r3 =>
adamc@910 49 acc' <- acc (r1 -- nm) (r2 -- nm) (r3 -- nm);
adamc@910 50 f [nm] [t] [rest] ! r1.nm r2.nm r3.nm acc')
adamc@910 51 (fn _ _ _ => return i)
adamc@910 52 [_] fl
adamc@910 53
adamc@905 54 fun mapR [K] [m] (_ : monad m) [tf :: K -> Type] [tr :: K -> Type]
adamc@905 55 (f : nm :: Name -> t :: K -> tf t -> m (tr t)) =
adamc@905 56 @@foldR [m] _ [tf] [fn r => $(map tr r)]
adamc@905 57 (fn [nm :: Name] [t :: K] [rest :: {K}] [[nm] ~ rest] (v : tf t)
adamc@905 58 (acc : $(map tr rest)) =>
adamc@905 59 v' <- f [nm] [t] v;
adamc@905 60 return (acc ++ {nm = v'}))
adamc@905 61 {}
adamc@937 62
adamc@937 63 fun mapR2 [K] [m] (_ : monad m) [tf1 :: K -> Type] [tf2 :: K -> Type] [tr :: K -> Type]
adamc@937 64 (f : nm :: Name -> t :: K -> tf1 t -> tf2 t -> m (tr t)) =
adamc@937 65 @@foldR2 [m] _ [tf1] [tf2] [fn r => $(map tr r)]
adamc@937 66 (fn [nm :: Name] [t :: K] [rest :: {K}] [[nm] ~ rest] (v1 : tf1 t) (v2 : tf2 t)
adamc@937 67 (acc : $(map tr rest)) =>
adamc@937 68 v' <- f [nm] [t] v1 v2;
adamc@937 69 return (acc ++ {nm = v'}))
adamc@937 70 {}