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| author |  Adam Chlipala <adam@chlipala.net> | 2011-08-15 10:22:09 -0400 |
|---|---|---|
| committer | Adam Chlipala <adam@chlipala.net> | 2011-08-15 10:22:09 -0400 |
| commit | da80f2aa1cd6326d0fc8621a5cfb0e7fd313e192 (patch) | |
| tree | d53efdcd64e016a6688ce67cb5b5b37c0758e9f6 | |
| parent | c58370c7b4a4cc6027baf7b6ebfcc1dcab181666 (diff) | |
List.mapXi
| -rw-r--r-- | lib/ur/list.ur | 10 | ||||
| -rw-r--r-- | lib/ur/list.urs | 2 |
2 files changed, 12 insertions, 0 deletions
diff --git a/lib/ur/list.ur b/lib/ur/list.ur index 2679d877..35440de2 100644 --- a/lib/ur/list.ur +++ b/lib/ur/list.ur @@ -133,6 +133,16 @@ fun mapX [a] [ctx ::: {Unit}] f = mapX' end +fun mapXi [a] [ctx ::: {Unit}] f = + let + fun mapX' i ls = + case ls of + [] => <xml/> + | x :: ls => <xml>{f i x}{mapX' (i + 1) ls}</xml> + in + mapX' 0 + end + fun mapM [m ::: (Type -> Type)] (_ : monad m) [a] [b] f = let fun mapM' acc ls = diff --git a/lib/ur/list.urs b/lib/ur/list.urs index 00bb5b48..851d74bc 100644 --- a/lib/ur/list.urs +++ b/lib/ur/list.urs @@ -26,6 +26,8 @@ val mapi : a ::: Type -> b ::: Type -> (int -> a -> b) -> t a -> t b val mapX : a ::: Type -> ctx ::: {Unit} -> (a -> xml ctx [] []) -> t a -> xml ctx [] [] +val mapXi : a ::: Type -> ctx ::: {Unit} -> (int -> a -> xml ctx [] []) -> t a -> xml ctx [] [] + val mapM : m ::: (Type -> Type) -> monad m -> a ::: Type -> b ::: Type -> (a -> m b) -> t a -> m (t b) |