hxt-9.2.2: A collection of tools for processing XML with Haskell.

Portability | portable
Stability | experimental
Maintainer | Uwe Schmidt (uwe@fh-wedel.de)
Safe Haskell | Safe-Infered

Text.XML.HXT.Arrow.XmlArrow

Description

Basic arrows for processing XML documents

All arrows use IO and a global state for options, errorhandling, ...

Synopsis

- class (Arrow a, ArrowList a, ArrowTree a) => ArrowXml a where
  - isText :: a XmlTree XmlTree
  - isBlob :: a XmlTree XmlTree
  - isCharRef :: a XmlTree XmlTree
  - isEntityRef :: a XmlTree XmlTree
  - isCmt :: a XmlTree XmlTree
  - isCdata :: a XmlTree XmlTree
  - isPi :: a XmlTree XmlTree
  - isXmlPi :: a XmlTree XmlTree
  - isElem :: a XmlTree XmlTree
  - isDTD :: a XmlTree XmlTree
  - isAttr :: a XmlTree XmlTree
  - isError :: a XmlTree XmlTree
  - isRoot :: a XmlTree XmlTree
  - hasText :: (String -> Bool) -> a XmlTree XmlTree
  - isWhiteSpace :: a XmlTree XmlTree
  - hasNameWith :: (QName -> Bool) -> a XmlTree XmlTree
  - hasQName :: QName -> a XmlTree XmlTree
  - hasName :: String -> a XmlTree XmlTree
  - hasLocalPart :: String -> a XmlTree XmlTree
  - hasNamePrefix :: String -> a XmlTree XmlTree
  - hasNamespaceUri :: String -> a XmlTree XmlTree
  - hasAttr :: String -> a XmlTree XmlTree
  - hasQAttr :: QName -> a XmlTree XmlTree
  - hasAttrValue :: String -> (String -> Bool) -> a XmlTree XmlTree
  - hasQAttrValue :: QName -> (String -> Bool) -> a XmlTree XmlTree
  - mkText :: a String XmlTree
  - mkBlob :: a Blob XmlTree
  - mkCharRef :: a Int XmlTree
  - mkEntityRef :: a String XmlTree
  - mkCmt :: a String XmlTree
  - mkCdata :: a String XmlTree
  - mkError :: Int -> a String XmlTree
  - mkElement :: QName -> a n XmlTree -> a n XmlTree -> a n XmlTree
  - mkAttr :: QName -> a n XmlTree -> a n XmlTree
  - mkPi :: QName -> a n XmlTree -> a n XmlTree
  - mkqelem :: QName -> [a n XmlTree] -> [a n XmlTree] -> a n XmlTree
  - mkelem :: String -> [a n XmlTree] -> [a n XmlTree] -> a n XmlTree
  - aelem :: String -> [a n XmlTree] -> a n XmlTree
  - selem :: String -> [a n XmlTree] -> a n XmlTree
  - eelem :: String -> a n XmlTree
  - root :: [a n XmlTree] -> [a n XmlTree] -> a n XmlTree
  - qattr :: QName -> a n XmlTree -> a n XmlTree
  - attr :: String -> a n XmlTree -> a n XmlTree
  - txt :: String -> a n XmlTree
  - blb :: Blob -> a n XmlTree
  - charRef :: Int -> a n XmlTree
  - entityRef :: String -> a n XmlTree
  - cmt :: String -> a n XmlTree
  - warn :: String -> a n XmlTree
  - err :: String -> a n XmlTree
  - fatal :: String -> a n XmlTree
  - spi :: String -> String -> a n XmlTree
  - sqattr :: QName -> String -> a n XmlTree
  - sattr :: String -> String -> a n XmlTree
  - getText :: a XmlTree String
  - getCharRef :: a XmlTree Int
  - getEntityRef :: a XmlTree String
  - getCmt :: a XmlTree String
  - getCdata :: a XmlTree String
  - getPiName :: a XmlTree QName
  - getPiContent :: a XmlTree XmlTree
  - getElemName :: a XmlTree QName
  - getAttrl :: a XmlTree XmlTree
  - getDTDPart :: a XmlTree DTDElem
  - getDTDAttrl :: a XmlTree Attributes
  - getAttrName :: a XmlTree QName
  - getErrorLevel :: a XmlTree Int
  - getErrorMsg :: a XmlTree String
  - getQName :: a XmlTree QName
  - getName :: a XmlTree String
  - getUniversalName :: a XmlTree String
  - getUniversalUri :: a XmlTree String
  - getLocalPart :: a XmlTree String
  - getNamePrefix :: a XmlTree String
  - getNamespaceUri :: a XmlTree String
  - getAttrValue :: String -> a XmlTree String
  - getAttrValue0 :: String -> a XmlTree String
  - getQAttrValue :: QName -> a XmlTree String
  - getQAttrValue0 :: QName -> a XmlTree String
  - changeText :: (String -> String) -> a XmlTree XmlTree
  - changeBlob :: (Blob -> Blob) -> a XmlTree XmlTree
  - changeCmt :: (String -> String) -> a XmlTree XmlTree
  - changeQName :: (QName -> QName) -> a XmlTree XmlTree
  - changeElemName :: (QName -> QName) -> a XmlTree XmlTree
  - changeAttrName :: (QName -> QName) -> a XmlTree XmlTree
  - changePiName :: (QName -> QName) -> a XmlTree XmlTree
  - changeAttrValue :: (String -> String) -> a XmlTree XmlTree
  - changeAttrl :: (XmlTrees -> XmlTrees -> XmlTrees) -> a XmlTree XmlTree -> a XmlTree XmlTree
  - setQName :: QName -> a XmlTree XmlTree
  - setElemName :: QName -> a XmlTree XmlTree
  - setAttrName :: QName -> a XmlTree XmlTree
  - setPiName :: QName -> a XmlTree XmlTree
  - setAttrl :: a XmlTree XmlTree -> a XmlTree XmlTree
  - addAttrl :: a XmlTree XmlTree -> a XmlTree XmlTree
  - addAttr :: String -> String -> a XmlTree XmlTree
  - removeAttr :: String -> a XmlTree XmlTree
  - removeQAttr :: QName -> a XmlTree XmlTree
  - processAttrl :: a XmlTree XmlTree -> a XmlTree XmlTree
  - processTopDownWithAttrl :: a XmlTree XmlTree -> a XmlTree XmlTree
  - (+=) :: a b XmlTree -> a b XmlTree -> a b XmlTree
  - xshow :: a n XmlTree -> a n String
  - xshowBlob :: a n XmlTree -> a n Blob
- class ArrowXml a => ArrowDTD a where
  - isDTDDoctype :: a XmlTree XmlTree
  - isDTDElement :: a XmlTree XmlTree
  - isDTDContent :: a XmlTree XmlTree
  - isDTDAttlist :: a XmlTree XmlTree
  - isDTDEntity :: a XmlTree XmlTree
  - isDTDPEntity :: a XmlTree XmlTree
  - isDTDNotation :: a XmlTree XmlTree
  - isDTDCondSect :: a XmlTree XmlTree
  - isDTDName :: a XmlTree XmlTree
  - isDTDPERef :: a XmlTree XmlTree
  - hasDTDAttr :: String -> a XmlTree XmlTree
  - getDTDAttrValue :: String -> a XmlTree String
  - setDTDAttrValue :: String -> String -> a XmlTree XmlTree
  - mkDTDElem :: DTDElem -> Attributes -> a n XmlTree -> a n XmlTree
  - mkDTDDoctype :: Attributes -> a n XmlTree -> a n XmlTree
  - mkDTDElement :: Attributes -> a n XmlTree
  - mkDTDEntity :: Attributes -> a n XmlTree
  - mkDTDPEntity :: Attributes -> a n XmlTree

# Documentation

class (Arrow a, ArrowList a, ArrowTree a) => ArrowXml a where

Arrows for processing `XmlTree`s

These arrows can be grouped into predicates, selectors, constructors, and transformers.

All predicates (tests) act like `none` for failure and `this` for success. A logical and can be formed by `a1 >>> a2` , a locical or by `a1 <+> a2` .

Selector arrows will fail, when applied to wrong input, e.g. selecting the text of a node with `getText` will fail when applied to a none text node.

Edit arrows will remain the input unchanged, when applied to wrong argument, e.g. editing the content of a text node with `changeText` applied to an element node will return the unchanged element node.

Methods

isText :: a XmlTree XmlTree

test for text nodes

isBlob :: a XmlTree XmlTree

isCharRef :: a XmlTree XmlTree

test for char reference, used during parsing

isEntityRef :: a XmlTree XmlTree

test for entity reference, used during parsing

isCmt :: a XmlTree XmlTree

test for comment

isCdata :: a XmlTree XmlTree

test for CDATA section, used during parsing

isPi :: a XmlTree XmlTree

test for processing instruction

isXmlPi :: a XmlTree XmlTree

test for processing instruction <?xml ...>

isElem :: a XmlTree XmlTree

test for element

isDTD :: a XmlTree XmlTree

test for DTD part, used during parsing

isAttr :: a XmlTree XmlTree

test for attribute tree

isError :: a XmlTree XmlTree

test for error message

isRoot :: a XmlTree XmlTree

test for root node (element with name "/")

hasText :: (String -> Bool) -> a XmlTree XmlTree

test for text nodes with text, for which a predicate holds

example: `hasText (all (`elem` " \t\n"))` check for text nodes with only whitespace content

isWhiteSpace :: a XmlTree XmlTree

test for text nodes with only white space

implemented with `hasTest`

hasNameWith :: (QName -> Bool) -> a XmlTree XmlTree

test whether a node (element, attribute, pi) has a name with a special property

hasQName :: QName -> a XmlTree XmlTree

test whether a node (element, attribute, pi) has a specific qualified name useful only after namespace propagation

hasName :: String -> a XmlTree XmlTree

test whether a node has a specific name (prefix:localPart ore localPart), generally useful, even without namespace handling

hasLocalPart :: String -> a XmlTree XmlTree

test whether a node has a specific name as local part, useful only after namespace propagation

hasNamePrefix :: String -> a XmlTree XmlTree

test whether a node has a specific name prefix, useful only after namespace propagation

hasNamespaceUri :: String -> a XmlTree XmlTree

test whether a node has a specific namespace URI useful only after namespace propagation

hasAttr :: String -> a XmlTree XmlTree

test whether an element node has an attribute node with a specific name

hasQAttr :: QName -> a XmlTree XmlTree

test whether an element node has an attribute node with a specific qualified name

hasAttrValue :: String -> (String -> Bool) -> a XmlTree XmlTree

test whether an element node has an attribute with a specific value

hasQAttrValue :: QName -> (String -> Bool) -> a XmlTree XmlTree

test whether an element node has an attribute with a qualified name and a specific value

mkText :: a String XmlTree

text node construction arrow

mkBlob :: a Blob XmlTree

blob node construction arrow

mkCharRef :: a Int XmlTree

char reference construction arrow, useful for document output

mkEntityRef :: a String XmlTree

entity reference construction arrow, useful for document output

mkCmt :: a String XmlTree

comment node construction, useful for document output

mkCdata :: a String XmlTree

CDATA construction, useful for document output

mkError :: Int -> a String XmlTree

error node construction, useful only internally

mkElement :: QName -> a n XmlTree -> a n XmlTree -> a n XmlTree

element construction: | the attributes and the content of the element are computed by applying arrows to the input

mkAttr :: QName -> a n XmlTree -> a n XmlTree

attribute node construction: | the attribute value is computed by applying an arrow to the input

mkPi :: QName -> a n XmlTree -> a n XmlTree

processing instruction construction: | the content of the processing instruction is computed by applying an arrow to the input

mkqelem :: QName -> [a n XmlTree] -> [a n XmlTree] -> a n XmlTree

convenient arrow for element construction, more comfortable variant of `mkElement`

example for simplifying `mkElement` :

     mkElement qn (a1 <+> ... <+> ai) (c1 <+> ... <+> cj)

equals

     mkqelem qn [a1,...,ai] [c1,...,cj]

mkelem :: String -> [a n XmlTree] -> [a n XmlTree] -> a n XmlTree

convenient arrow for element construction with strings instead of qualified names as element names, see also `mkElement` and `mkelem`

aelem :: String -> [a n XmlTree] -> a n XmlTree

convenient arrow for element constrution with attributes but without content, simple variant of `mkelem` and `mkElement`

selem :: String -> [a n XmlTree] -> a n XmlTree

convenient arrow for simple element constrution without attributes, simple variant of `mkelem` and `mkElement`

eelem :: String -> a n XmlTree

convenient arrow for constrution of empty elements without attributes, simple variant of `mkelem` and `mkElement`

root :: [a n XmlTree] -> [a n XmlTree] -> a n XmlTree

construction of an element node with name "/" for document roots

qattr :: QName -> a n XmlTree -> a n XmlTree

alias for `mkAttr`

attr :: String -> a n XmlTree -> a n XmlTree

convenient arrow for attribute constrution, simple variant of `mkAttr`

txt :: String -> a n XmlTree

constant arrow for text nodes

blb :: Blob -> a n XmlTree

constant arrow for blob nodes

charRef :: Int -> a n XmlTree

constant arrow for char reference nodes

entityRef :: String -> a n XmlTree

constant arrow for entity reference nodes

cmt :: String -> a n XmlTree

constant arrow for comment

warn :: String -> a n XmlTree

constant arrow for warning

err :: String -> a n XmlTree

constant arrow for errors

fatal :: String -> a n XmlTree

constant arrow for fatal errors

spi :: String -> String -> a n XmlTree

constant arrow for simple processing instructions, see `mkPi`

sqattr :: QName -> String -> a n XmlTree

constant arrow for attribute nodes, attribute name is a qualified name and value is a text, | see also `mkAttr`, `qattr`, `attr`

sattr :: String -> String -> a n XmlTree

constant arrow for attribute nodes, attribute name and value are | given by parameters, see `mkAttr`

getText :: a XmlTree String

select the text of a text node

getCharRef :: a XmlTree Int

select the value of a char reference

getEntityRef :: a XmlTree String

select the name of a entity reference node

getCmt :: a XmlTree String

select the comment of a comment node

getCdata :: a XmlTree String

select the content of a CDATA node

getPiName :: a XmlTree QName

select the name of a processing instruction

getPiContent :: a XmlTree XmlTree

select the content of a processing instruction

getElemName :: a XmlTree QName

select the name of an element node

getAttrl :: a XmlTree XmlTree

select the attribute list of an element node

getDTDPart :: a XmlTree DTDElem

select the DTD type of a DTD node

getDTDAttrl :: a XmlTree Attributes

select the DTD attributes of a DTD node

getAttrName :: a XmlTree QName

select the name of an attribute

getErrorLevel :: a XmlTree Int

select the error level (c_warn, c_err, c_fatal) from an error node

getErrorMsg :: a XmlTree String

select the error message from an error node

getQName :: a XmlTree QName

select the qualified name from an element, attribute or pi

getName :: a XmlTree String

select the prefix:localPart or localPart from an element, attribute or pi

getUniversalName :: a XmlTree String

select the univeral name ({namespace URI} ++ localPart)

getUniversalUri :: a XmlTree String

select the univeral name (namespace URI ++ localPart)

getLocalPart :: a XmlTree String

select the local part

getNamePrefix :: a XmlTree String

select the name prefix

getNamespaceUri :: a XmlTree String

select the namespace URI

getAttrValue :: String -> a XmlTree String

select the value of an attribute of an element node, always succeeds with empty string as default value ""

getAttrValue0 :: String -> a XmlTree String

like `getAttrValue`, but fails if the attribute does not exist

getQAttrValue :: QName -> a XmlTree String

like `getAttrValue`, but select the value of an attribute given by a qualified name, always succeeds with empty string as default value ""

getQAttrValue0 :: QName -> a XmlTree String

like `getQAttrValue`, but fails if attribute does not exist

changeText :: (String -> String) -> a XmlTree XmlTree

edit the string of a text node

changeBlob :: (Blob -> Blob) -> a XmlTree XmlTree

edit the blob of a blob node

changeCmt :: (String -> String) -> a XmlTree XmlTree

edit the comment string of a comment node

changeQName :: (QName -> QName) -> a XmlTree XmlTree

edit an element-, attribute- or pi- name

changeElemName :: (QName -> QName) -> a XmlTree XmlTree

edit an element name

changeAttrName :: (QName -> QName) -> a XmlTree XmlTree

edit an attribute name

changePiName :: (QName -> QName) -> a XmlTree XmlTree

edit a pi name

changeAttrValue :: (String -> String) -> a XmlTree XmlTree

edit an attribute value

changeAttrl :: (XmlTrees -> XmlTrees -> XmlTrees) -> a XmlTree XmlTree -> a XmlTree XmlTree

edit an attribute list of an element node

setQName :: QName -> a XmlTree XmlTree

replace an element, attribute or pi name

setElemName :: QName -> a XmlTree XmlTree

replace an element name

setAttrName :: QName -> a XmlTree XmlTree

replace an attribute name

setPiName :: QName -> a XmlTree XmlTree

replace an element name

setAttrl :: a XmlTree XmlTree -> a XmlTree XmlTree

replace an atribute list of an element node

addAttrl :: a XmlTree XmlTree -> a XmlTree XmlTree

add a list of attributes to an element

addAttr :: String -> String -> a XmlTree XmlTree

add (or replace) an attribute

removeAttr :: String -> a XmlTree XmlTree

remove an attribute

removeQAttr :: QName -> a XmlTree XmlTree

remove an attribute with a qualified name

processAttrl :: a XmlTree XmlTree -> a XmlTree XmlTree

process the attributes of an element node with an arrow

processTopDownWithAttrl :: a XmlTree XmlTree -> a XmlTree XmlTree

process a whole tree inclusive attribute list of element nodes see also: `processTopDown`

(+=) :: a b XmlTree -> a b XmlTree -> a b XmlTree

convenient op for adding attributes or children to a node

usage: `tf += cf`

the `tf` arrow computes an element node, and all trees computed by `cf` are added to this node, if a tree is an attribute, it is inserted in the attribute list else it is appended to the content list.

attention: do not build long content list this way because `+=` is implemented by ++

examples:

     eelem "a"
       += sattr "href" "page.html"
       += sattr "name" "here"
       += txt "look here"

is the same as

     mkelem [ sattr "href" "page.html"
            , sattr "name" "here"
            ]
            [ txt "look here" ]

and results in the XML fragment: <a href="page.html" name="here">look here</a>

advantage of the `+=` operator is, that attributes and content can be added any time step by step. if `tf` computes a whole list of trees, e.g. a list of "td" or "tr" elements, the attributes or content is added to all trees. useful for adding "class" or "style" attributes to table elements.

xshow :: a n XmlTree -> a n String

apply an arrow to the input and convert the resulting XML trees into a string representation

xshowBlob :: a n XmlTree -> a n Blob

apply an arrow to the input and convert the resulting XML trees into a string representation

Instances

ArrowXml LA |
ArrowXml IOLA |
ArrowXml (SLA s) |
ArrowXml (IOSLA s) |

class ArrowXml a => ArrowDTD a where

Document Type Definition arrows

These are separated, because they are not needed for document processing, only when processing the DTD, e.g. for generating access funtions for the toolbox from a DTD (se example DTDtoHaskell in the examples directory)

Methods

isDTDDoctype :: a XmlTree XmlTree

isDTDElement :: a XmlTree XmlTree

isDTDContent :: a XmlTree XmlTree

isDTDAttlist :: a XmlTree XmlTree

isDTDEntity :: a XmlTree XmlTree

isDTDPEntity :: a XmlTree XmlTree

isDTDNotation :: a XmlTree XmlTree

isDTDCondSect :: a XmlTree XmlTree

isDTDName :: a XmlTree XmlTree

isDTDPERef :: a XmlTree XmlTree

hasDTDAttr :: String -> a XmlTree XmlTree

getDTDAttrValue :: String -> a XmlTree String

setDTDAttrValue :: String -> String -> a XmlTree XmlTree

mkDTDElem :: DTDElem -> Attributes -> a n XmlTree -> a n XmlTree

mkDTDDoctype :: Attributes -> a n XmlTree -> a n XmlTree

mkDTDElement :: Attributes -> a n XmlTree

mkDTDEntity :: Attributes -> a n XmlTree

mkDTDPEntity :: Attributes -> a n XmlTree

Instances

ArrowDTD LA |
ArrowDTD IOLA |
ArrowDTD (SLA s) |
ArrowDTD (IOSLA s) |