| License | BSD-style (see the file LICENSE) |
|---|---|
| Maintainer | sjoerd@w3future.com |
| Safe Haskell | Safe |
| Language | Haskell2010 |
Data.Traversable.Square
Description
Synopsis
- traverse :: (Traversable t, Applicative f) => Square '[Star f] '[Star f] '[t] '[t]
- sequence :: (Traversable t, Applicative f) => Square '[] '[] '[f, t] '[t, f]
Documentation
traverse :: (Traversable t, Applicative f) => Square '[Star f] '[Star f] '[t] '[t] Source #
+--t--+ | v | f>-T->f | v | +--t--+
traverse as a square.
Naturality law:
+-----t--+ +--t-----+ | v | | v | f>-@->T->g === f>-T->@->g | v | | v | +-----t--+ +--t-----+
Identity law:
+--t--+ +--t--+ | v | | | | | T | === | v | | v | | | | +--t--+ +--t--+
Composition law:
+--t--+ +--t--+ | v | | v | f>-T->f f>\|/>f | v | === | T | g>-T->g g>/|\>g | v | | v | +--t--+ +--t--+
sequence :: (Traversable t, Applicative f) => Square '[] '[] '[f, t] '[t, f] Source #
+-f-t---+ | v v | | \-@-\ | | v v | +---t-f-+
sequence = toRight ||| traverse ||| fromLeft