Modulepandoc-types-1.23.1.2Haskell2010

Text.Pandoc.Walk

Functions for manipulating Pandoc documents or extracting information from them by walking the Pandoc structure (or intermediate structures like '[Block]' or '[Inline]'. These are faster (by a factor of four or five) than the generic functions defined in Text.Pandoc.Generic.

Here's a simple example, defining a function that replaces all the level 3+ headers in a document with regular paragraphs in ALL CAPS:

import Text.Pandoc.Definition
import Text.Pandoc.Walk
import Data.Char (toUpper)

modHeader :: Block -> Block
modHeader (Header n _ xs) | n >= 3 = Para $ walk allCaps xs
modHeader x = x

allCaps :: Inline -> Inline
allCaps (Str xs) = Str $ map toUpper xs
allCaps x = x

changeHeaders :: Pandoc -> Pandoc
changeHeaders = walk modHeader

query can be used, for example, to compile a list of URLs linked to in a document:

extractURL :: Inline -> [Text]
extractURL (Link _ _ (u,_)) = [u]
extractURL (Image _ _ (u,_)) = [u]
extractURL _ = []

extractURLs :: Pandoc -> [Text]
extractURLs = query extractURL

Synopsis

class Walkable
value queryBlock
value queryCaption
value queryRow
value queryTableHead
value queryTableBody
value queryTableFoot
value queryCell
value queryCitation
value queryInline
value queryMetaValue
value queryMetaValue'
value queryPandoc
value walkBlockM
value walkCaptionM
value walkRowM
value walkTableHeadM
value walkTableBodyM
value walkTableFootM
value walkCellM
value walkCitationM
value walkInlineM
value walkMetaValueM
value walkMetaValueM'
value walkPandocM

Packagepandoc-types-1.23.1.2
Exports25
LanguageHaskell2010
LicenceBSD-3-Clause
SourceWalk.hs

classclass Walkable a b where

Methods

walk :: (a -> a) -> b -> b
walk f x walks the structure x (bottom up) and replaces every occurrence of an a with the result of applying f to it.
walkM :: (Monad m, Applicative m, Functor m) => (a -> m a) -> b -> m b
A monadic version of walk.
query :: Monoid c => (a -> c) -> b -> c
query f x walks the structure x (bottom up) and applies f to every a, appending the results.

Instances58Walkable, …

Walkable Block BlockDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable Block CaptionDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable Block CellDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable Block CitationDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable Block InlineDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable Block MetaDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable Block MetaValueDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable Block PandocDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable Block RowDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable Block TableBodyDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable Block TableFootDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable Block TableHeadDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable Inline BlockDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable Inline CaptionDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable Inline CellDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable Inline CitationDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable Inline InlineDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable Inline MetaDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable Inline MetaValueDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable Inline PandocDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable Inline RowDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable Inline TableBodyDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable Inline TableFootDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable Inline TableHeadDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable Meta MetaDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable Meta PandocDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable MetaValue MetaDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable MetaValue MetaValueDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable MetaValue PandocDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable Pandoc PandocDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
(Foldable t, Traversable t, Walkable a b) => Walkable a (t b)Defined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
(Walkable a b, Walkable a c) => Walkable a (b, c)Defined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable [Block] BlockDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable [Block] CaptionDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable [Block] CellDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable [Block] CitationDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable [Block] InlineDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable [Block] MetaDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable [Block] MetaValueDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable [Block] PandocDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable [Block] RowDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable [Block] TableBodyDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable [Block] TableFootDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable [Block] TableHeadDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable [Inline] BlockDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable [Inline] CaptionDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable [Inline] CellDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable [Inline] CitationDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable [Inline] InlineDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable [Inline] MetaDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable [Inline] MetaValueDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable [Inline] PandocDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable [Inline] RowDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable [Inline] TableBodyDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable [Inline] TableFootDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable [Inline] TableHeadDefined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable [Block] [Block]Defined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk
Walkable [Inline] [Inline]Defined in pandoc-types-1.23.1.2 · Text.Pandoc.Walk

valuequeryBlock

:: (Walkable a Citation, Walkable a [Block], Walkable a Row, Walkable a Caption, Walkable a TableHead, Walkable a TableBody, Walkable a TableFoot, Walkable a [Inline], Monoid c)
=> a -> c
-> Block
-> c