ExRoseTree.Zipper.Location (ExRoseTree v0.1.4)

View Source

A Location in the path from the root of the ExRoseTree.Zipper to its current context.

Summary

Guards

location?(value)

Types

t()

A Location is made up of the term of an ExRoseTree with lists of prev and next siblings.

Functions

all_locations?(values)

Returns whether a list of values are all Locations or not. Will return true if passed an empty list.

index_of_term(location)

Returns the index of the Location in relation to its siblings.

map_term(location, map_fn)

Applies the given function to the Location's term field.

new(item, opts \\ [])

Builds a new Location given a term() or an ExRoseTree as the first argument, and optional :prev and :next keywords of lists of ExRoseTrees.

Guards

location?(value)

(macro)

Types

t()

@type t() :: %ExRoseTree.Zipper.Location{
  next: [ExRoseTree.t()],
  prev: [ExRoseTree.t()],
  term: term()
}

A Location is made up of the term of an ExRoseTree with lists of prev and next siblings.

  • term is an ExRoseTree term.
  • prev is a list of ExRoseTrees. They are the siblings that occur prior the term. It is reversed such that the head of the list is the nearest previous sibling.
  • next is a list of ExRoseTrees. They are the siblings that occur after the term.

Functions

all_locations?(values)

@spec all_locations?([t()]) :: boolean()

Returns whether a list of values are all Locations or not. Will return true if passed an empty list.

Examples

iex> locs = for loc <- [5,4,3,2,1], do: ExRoseTree.Zipper.Location.new(loc)
...> ExRoseTree.Zipper.Location.all_locations?(locs)
true

index_of_term(location)

@spec index_of_term(t()) :: non_neg_integer()

Returns the index of the Location in relation to its siblings.

Examples

iex> trees = for t <- [5,4,3,2,1], do: ExRoseTree.new(t)
...> loc = ExRoseTree.Zipper.Location.new(6, prev: trees, next: [])
...> ExRoseTree.Zipper.Location.index_of_term(loc)
5

map_term(location, map_fn)

@spec map_term(t(), (term() -> term())) :: t()

Applies the given function to the Location's term field.

Examples

iex> loc = ExRoseTree.Zipper.Location.new(5, prev: [], next: [])
...> ExRoseTree.Zipper.Location.map_term(loc, &(&1*2))
%ExRoseTree.Zipper.Location{prev: [], term: 10, next: []}

new(item, opts \\ [])

@spec new(
  ExRoseTree.t() | term(),
  keyword()
) :: t() | nil

Builds a new Location given a term() or an ExRoseTree as the first argument, and optional :prev and :next keywords of lists of ExRoseTrees.

If the first argument is an ExRoseTree, it will unwrap its term element.

Examples

iex> ExRoseTree.Zipper.Location.new(5, prev: [], next: [])
%ExRoseTree.Zipper.Location{prev: [], term: 5, next: []}

iex> tree = ExRoseTree.new(4)
...> ExRoseTree.Zipper.Location.new(5, prev: [tree], next: [])
%ExRoseTree.Zipper.Location{
  prev: [
    %ExRoseTree{term: 4, children: []}
  ],
  term: 5,
  next: []
}