lens-4.3.3: Lenses, Folds and Traversals

Portabilitynon-portable
Stabilityexperimental
MaintainerEdward Kmett <ekmett@gmail.com>
Safe HaskellTrustworthy

Data.Text.Lens

Description

 

Synopsis

Documentation

class IsText t whereSource

Traversals for strict or lazy Text

Methods

packed :: Iso' String tSource

This isomorphism can be used to pack (or unpack) strict or lazy Text. 

 pack x ≡ x ^. packed
 unpack x ≡ x ^. from packed
 packed ≡ from unpacked

builder :: Iso' t BuilderSource

Convert between strict or lazy Text and a Builder. 

 fromText x ≡ x ^. builder

text :: IndexedTraversal' Int t CharSource

Traverse the individual characters in strict or lazy Text. 

 text = unpacked . traversed

Instances

unpacked :: IsText t => Iso' t StringSource

This isomorphism can be used to unpack (or pack) both strict or lazy Text. 

 unpack x ≡ x ^. unpacked
 pack x ≡ x ^. from unpacked

This Iso is provided for notational convenience rather than out of great need, since 

 unpacked ≡ from packed

_Text :: IsText t => Iso' t StringSource

This is an alias for unpacked that makes it clearer how to use it with ('#'). 

 _Text = from packed

>>> _Text # "hello" :: Strict.Text
"hello"