Module: Fr::TZipper

Defined in:
lib/fr/tzipper.rb,
lib/fr/tzipper/node.rb,
lib/fr/tzipper/path.rb,
lib/fr/tzipper/root_cursor.rb,
lib/fr/tzipper/edited_cursor.rb,
lib/fr/tzipper/abstract_cursor.rb,
lib/fr/tzipper/dangling_cursor.rb,
lib/fr/tzipper/memoized_cursor.rb

Defined Under Namespace

Classes: AbstractCursor, AbstractPath, DanglingCursor, EditedCursor, Hole, MemoizedCursor, Node, RootCursor

Constant Summary collapse

Root = 
Class.new(AbstractPath) do

  # @return self
  def parent
    self
  end

  # (see AbstractPath#left)
  def left
    []
  end

  # (see AbstractPath#right)
  def right
    []
  end

  # (see AbstractPath#last?)
  # @return true
  def last?
    true
  end

  # (see AbstractPath#first?)
  # @return true
  def first?
    true
  end

  # (see AbstractPath#depth)
  def depth
    0
  end

  def position
    nil
  end

  # @return [String]
  def inspect
    "root"
  end
end.new

Class Method Summary collapse

Class Method Details

.build(node) ⇒ AbstractCursor

Constructors a zipper for traversing the given tree or subtree. The ‘node` value can be any structure where

node#children
  an array of child nodes

node#leaf?
  true if the node is not allowed have children

node#copy(children: [...])
  creates a new node with the given children

node#cons(xs)
  returns a new list [node, *xs]

Returns:



33
34
35
 
# File 'lib/fr/tzipper.rb', line 33

def build(node)
  Fr::TZipper::RootCursor.new(node)
end