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Diffstat (limited to 'src/Common/Helper.v')
-rw-r--r-- | src/Common/Helper.v | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/src/Common/Helper.v b/src/Common/Helper.v new file mode 100644 index 0000000..292d011 --- /dev/null +++ b/src/Common/Helper.v @@ -0,0 +1,21 @@ +Module Option. + +Definition default {T : Type} (x : T) (u : option T) : T := + match u with + | Some y => y + | _ => x + end. + +Definition map {S : Type} {T : Type} (f : S -> T) (u : option S) : option T := + match u with + | Some y => Some (f y) + | _ => None + end. + +Definition liftA2 {T : Type} (f : T -> T -> T) (a : option T) (b : option T) : option T := + match a with + | Some x => map (f x) b + | _ => None + end. + +End Option. |