| Copyright | (C) 2012 Edward Kmett |
|---|---|
| License | BSD-style (see the file LICENSE) |
| Maintainer | Edward Kmett <ekmett@gmail.com> |
| Stability | experimental |
| Portability | portable |
| Safe Haskell | Safe-Inferred |
| Language | Haskell98 |
Bound.Term
Description
- substitute :: (Monad f, Eq a) => a -> f a -> f a -> f a
- substituteVar :: (Functor f, Eq a) => a -> a -> f a -> f a
- isClosed :: Foldable f => f a -> Bool
- closed :: Traversable f => f a -> Maybe (f b)
Documentation
substitute :: (Monad f, Eq a) => a -> f a -> f a -> f a Source
substitute a p wa with p in w.
>>>substitute "hello" ["goodnight","Gracie"] ["hello","!!!"]["goodnight","Gracie","!!!"]
substituteVar :: (Functor f, Eq a) => a -> a -> f a -> f a Source
substituteVar a b wa with another free variable b in w.
>>>substituteVar "Alice" "Bob" ["Alice","Bob","Charlie"]["Bob","Bob","Charlie"]
isClosed :: Foldable f => f a -> Bool Source
A closed term has no free variables.
>>>isClosed []True
>>>isClosed [1,2,3]False
closed :: Traversable f => f a -> Maybe (f b) Source
If a term has no free variables, you can freely change the type of free variables it is parameterized on.
>>>closed [12]Nothing
>>>closed ""Just []
>>>:t closed ""closed "" :: Maybe [b]