module Hashie::Extensions::DeepLocate

Public Class Methods

deep_locate(comparator, object) click to toggle source

The module level implementation of deep_locate, incase you do not want to include/extend the base datastructure. For further examples please see deep_locate.

@example

books = [
  {
    title: "Ruby for beginners",
    pages: 120
  },
  ...
]

Hashie::Extensions::DeepLocate.deep_locate -> (key, value, object) { key == :title }, books
# => [{:title=>"Ruby for beginners", :pages=>120}, ...]
# File lib/hashie/extensions/deep_locate.rb, line 19
def self.deep_locate(comparator, object)
  comparator = _construct_key_comparator(comparator, object) unless comparator.respond_to?(:call)

  _deep_locate(comparator, object)
end

Private Class Methods

_construct_key_comparator(search_key, object) click to toggle source
# File lib/hashie/extensions/deep_locate.rb, line 66
def self._construct_key_comparator(search_key, object)
  search_key = search_key.to_s if defined?(::ActiveSupport::HashWithIndifferentAccess) && object.is_a?(::ActiveSupport::HashWithIndifferentAccess)
  search_key = search_key.to_s if object.respond_to?(:indifferent_access?) && object.indifferent_access?

  lambda do |non_callable_object|
    ->(key, _, _) { key == non_callable_object }
  end.call(search_key)
end
_deep_locate(comparator, object, result = []) click to toggle source
# File lib/hashie/extensions/deep_locate.rb, line 75
def self._deep_locate(comparator, object, result = [])
  if object.is_a?(::Enumerable)
    if object.any? { |value| _match_comparator?(value, comparator, object) }
      result.push object
    end
    (object.respond_to?(:values) ? object.values : object.entries).each do |value|
      _deep_locate(comparator, value, result)
    end
  end

  result
end
_match_comparator?(value, comparator, object) click to toggle source
# File lib/hashie/extensions/deep_locate.rb, line 88
def self._match_comparator?(value, comparator, object)
  if object.is_a?(::Hash)
    key, value = value
  else
    key = nil
  end

  comparator.call(key, value, object)
end

Public Instance Methods

deep_locate(comparator) click to toggle source

Performs a depth-first search on deeply nested data structures for a given comparator callable and returns each Enumerable, for which the callable returns true for at least one the its elements.

@example

books = [
  {
    title: "Ruby for beginners",
    pages: 120
  },
  {
    title: "CSS for intermediates",
    pages: 80
  },
  {
    title: "Collection of ruby books",
    books: [
      {
        title: "Ruby for the rest of us",
        pages: 576
      }
    ]
  }
]

books.extend(Hashie::Extensions::DeepLocate)

# for ruby 1.9 leave *no* space between the lambda rocket and the braces
# http://ruby-journal.com/becareful-with-space-in-lambda-hash-rocket-syntax-between-ruby-1-dot-9-and-2-dot-0/

books.deep_locate -> (key, value, object) { key == :title && value.include?("Ruby") }
# => [{:title=>"Ruby for beginners", :pages=>120}, {:title=>"Ruby for the rest of us", :pages=>576}]

books.deep_locate -> (key, value, object) { key == :pages && value <= 120 }
# => [{:title=>"Ruby for beginners", :pages=>120}, {:title=>"CSS for intermediates", :pages=>80}]
# File lib/hashie/extensions/deep_locate.rb, line 60
def deep_locate(comparator)
  Hashie::Extensions::DeepLocate.deep_locate(comparator, self)
end