Text.XmlHtml.Cursor

A zipper for navigating and modifying XML trees. This is nearly the same exposed interface as the xml package in Text.XML.Light.Cursor, with modifications as needed to adapt to different types.

Cursor type

data Cursor

A zipper for XML document forests.

Instances

Eq Cursor

Conversion to and from cursors

fromNode :: Node -> Cursor

Builds a Cursor for navigating a tree. That is, a forest with a single root Node.

fromNodes :: [Node] -> Maybe Cursor

Builds a Cursor for navigating a forest with the given list of roots. The cursor is initially positioned at the left-most node. Gives Nothing if the list is empty.

topNode :: Cursor -> Node

Retrieves the root node containing the current cursor position.

topNodes :: Cursor -> [Node]

Retrieves the entire forest of Nodes corresponding to a Cursor.

current :: Cursor -> Node

Retrieves the current node of a Cursor

siblings :: Cursor -> [Node]

Retrieves a list of the Nodes at the same level as the current position of a cursor, including the current node.

Cursor navigation

parent :: Cursor -> Maybe Cursor

Navigates a Cursor to its parent in the document.

root :: Cursor -> Cursor

Navigates a Cursor up through parents to reach the root level.

getChild :: Int -> Cursor -> Maybe Cursor

Navigates a Cursor down to the indicated child index.

firstChild :: Cursor -> Maybe Cursor

Navigates a Cursor down to its first child.

lastChild :: Cursor -> Maybe Cursor

Navigates a Cursor down to its last child.

left :: Cursor -> Maybe Cursor

Moves a Cursor to its left sibling.

right :: Cursor -> Maybe Cursor

Moves a Cursor to its right sibling.

nextDF :: Cursor -> Maybe Cursor

Moves a Cursor to the next node encountered in a depth-first search. If it has children, this is equivalent to firstChild. Otherwise, if it has a right sibling, then this is equivalent to right. Otherwise, the cursor moves to the first right sibling of one of its parents.

Search

findChild :: (Cursor -> Bool) -> Cursor -> Maybe Cursor

Navigates a Cursor to the first child that matches the predicate.

findLeft :: (Cursor -> Bool) -> Cursor -> Maybe Cursor

Navigates a Cursor to the nearest left sibling that matches a predicate.

findRight :: (Cursor -> Bool) -> Cursor -> Maybe Cursor

Navigates a Cursor to the nearest right sibling that matches a predicate.

findRec :: (Cursor -> Bool) -> Cursor -> Maybe Cursor

Does a depth-first search for a descendant matching the predicate. This can match the current cursor position.

Node classification

isRoot :: Cursor -> Bool

Determines if the Cursor is at a root node.

isFirst :: Cursor -> Bool

Determines if the Cursor is at a first child.

isLast :: Cursor -> Bool

Determines if the Cursor is at a last child.

isLeaf :: Cursor -> Bool

Determines if the Cursor is at a leaf node.

isChild :: Cursor -> Bool

Determines if the Cursor is at a child node (i.e., if it has a parent).

hasChildren :: Cursor -> Bool

Determines if the Cursor is at a non-leaf node (i.e., if it has children).

getNodeIndex :: Cursor -> Int

Gets the index of the Cursor among its siblings.

Updates

setNode :: Node -> Cursor -> Cursor

Replaces the current node.

modifyNode :: (Node -> Node) -> Cursor -> Cursor

Modifies the current node by applying a function.

modifyNodeM :: Functor m => (Node -> m Node) -> Cursor -> m Cursor

Modifies the current node by applying an action in some functor.

Insertions

insertLeft :: Node -> Cursor -> Cursor

Inserts a new Node to the left of the current position.

insertRight :: Node -> Cursor -> Cursor

Inserts a new Node to the right of the current position.

insertManyLeft :: [Node] -> Cursor -> Cursor

Inserts a list of new Nodes to the left of the current position.

insertManyRight :: [Node] -> Cursor -> Cursor

Inserts a list of new Nodes to the right of the current position.

insertFirstChild :: Node -> Cursor -> Maybe Cursor

Inserts a Node as the first child of the current element.

insertLastChild :: Node -> Cursor -> Maybe Cursor

Inserts a Node as the last child of the current element.

insertManyFirstChild :: [Node] -> Cursor -> Maybe Cursor

Inserts a list of Nodes as the first children of the current element.

insertManyLastChild :: [Node] -> Cursor -> Maybe Cursor

Inserts a list of Nodes as the last children of the current element.

insertGoLeft :: Node -> Cursor -> Cursor

Inserts a new Node to the left of the current position, and moves left to the new node.

insertGoRight :: Node -> Cursor -> Cursor

Inserts a new Node to the right of the current position, and moves right to the new node.

Deletions

removeLeft :: Cursor -> Maybe (Node, Cursor)

Removes the Node to the left of the current position, if any.

removeRight :: Cursor -> Maybe (Node, Cursor)

Removes the Node to the right of the current position, if any.

removeGoLeft :: Cursor -> Maybe Cursor

Removes the current Node, and moves the Cursor to its left sibling, if any.

removeGoRight :: Cursor -> Maybe Cursor

Removes the current Node, and moves the Cursor to its right sibling, if any.

removeGoUp :: Cursor -> Maybe Cursor

Removes the current Node, and moves the Cursor to its parent, if any.