Class: ActiveSupport::HashWithIndifferentAccess

Inherits:
Hash
  • Object
show all
Defined in:
lib/active_support/hash_with_indifferent_access.rb

Class Method Summary collapse

Instance Method Summary collapse

Methods inherited from Hash

#as_json, #assert_valid_keys, #deep_dup, #deep_merge, #deep_merge!, #diff, #encode_json, #except, #except!, #extract!, from_xml, #slice, #slice!, #symbolize_keys!, #to_param, #to_xml

Constructor Details

#initialize(constructor = {}) ⇒ HashWithIndifferentAccess

Returns a new instance of HashWithIndifferentAccess.



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# File 'lib/active_support/hash_with_indifferent_access.rb', line 23

def initialize(constructor = {})
  if constructor.is_a?(Hash)
    super()
    update(constructor)
  else
    super(constructor)
  end
end

Class Method Details

.new_from_hash_copying_default(hash) ⇒ Object 



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# File 'lib/active_support/hash_with_indifferent_access.rb', line 40

def self.new_from_hash_copying_default(hash)
  new(hash).tap do |new_hash|
    new_hash.default = hash.default
  end
end

Instance Method Details

#[]=(key, value) ⇒ Object Also known as: store

Assigns a new value to the hash:

hash = HashWithIndifferentAccess.new
hash[:key] = "value"



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# File 'lib/active_support/hash_with_indifferent_access.rb', line 54

def []=(key, value)
  regular_writer(convert_key(key), convert_value(value))
end

#default(key = nil) ⇒ Object 



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# File 'lib/active_support/hash_with_indifferent_access.rb', line 32

def default(key = nil)
  if key.is_a?(Symbol) && include?(key = key.to_s)
    self[key]
  else
    super
  end
end

#delete(key) ⇒ Object

Removes a specified key from the hash.



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# File 'lib/active_support/hash_with_indifferent_access.rb', line 146

def delete(key)
  super(convert_key(key))
end

#dup ⇒ Object

Returns an exact copy of the hash.



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# File 'lib/active_support/hash_with_indifferent_access.rb', line 123

def dup
  self.class.new(self).tap do |new_hash|
    new_hash.default = default
  end
end

#extractable_options? ⇒ Boolean

Always returns true, so that Array#extract_options! finds members of this class.

Returns:

  • (Boolean) 


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# File 'lib/active_support/hash_with_indifferent_access.rb', line 11

def extractable_options?
  true
end

#fetch(key, *extras) ⇒ Object

Same as Hash#fetch where the key passed as argument can be either a string or a symbol:

counters = HashWithIndifferentAccess.new
counters[:foo] = 1

counters.fetch("foo")          # => 1
counters.fetch(:bar, 0)        # => 0
counters.fetch(:bar) {|key| 0} # => 0
counters.fetch(:zoo)           # => KeyError: key not found: "zoo"



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# File 'lib/active_support/hash_with_indifferent_access.rb', line 107

def fetch(key, *extras)
  super(convert_key(key), *extras)
end

#key?(key) ⇒ Boolean Also known as: include?, has_key?, member?

Checks the hash for a key matching the argument passed in:

hash = HashWithIndifferentAccess.new
hash["key"] = "value"
hash.key? :key  # => true
hash.key? "key" # => true

Returns:

  • (Boolean) 


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# File 'lib/active_support/hash_with_indifferent_access.rb', line 88

def key?(key)
  super(convert_key(key))
end

#merge(hash) ⇒ Object

Merges the instantized and the specified hashes together, giving precedence to the values from the second hash. Does not overwrite the existing hash.



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# File 'lib/active_support/hash_with_indifferent_access.rb', line 131

def merge(hash)
  self.dup.update(hash)
end

#nested_under_indifferent_access ⇒ Object 



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# File 'lib/active_support/hash_with_indifferent_access.rb', line 19

def nested_under_indifferent_access
  self
end

#regular_update ⇒ Object 



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# File 'lib/active_support/hash_with_indifferent_access.rb', line 47

alias_method :regular_update, :update

#regular_writer ⇒ Object 



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# File 'lib/active_support/hash_with_indifferent_access.rb', line 46

alias_method :regular_writer, :[]=

#reverse_merge(other_hash) ⇒ Object

Performs the opposite of merge, with the keys and values from the first hash taking precedence over the second. This overloaded definition prevents returning a regular hash, if reverse_merge is called on a HashWithDifferentAccess.



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# File 'lib/active_support/hash_with_indifferent_access.rb', line 137

def reverse_merge(other_hash)
  super self.class.new_from_hash_copying_default(other_hash)
end

#reverse_merge!(other_hash) ⇒ Object 



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# File 'lib/active_support/hash_with_indifferent_access.rb', line 141

def reverse_merge!(other_hash)
  replace(reverse_merge( other_hash ))
end

#stringify_keys ⇒ Object 



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# File 'lib/active_support/hash_with_indifferent_access.rb', line 151

def stringify_keys; dup end

#stringify_keys! ⇒ Object 



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# File 'lib/active_support/hash_with_indifferent_access.rb', line 150

def stringify_keys!; self end

#symbolize_keys ⇒ Object 



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# File 'lib/active_support/hash_with_indifferent_access.rb', line 153

def symbolize_keys; to_hash.symbolize_keys end

#to_hash ⇒ Object

Convert to a Hash with String keys.



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# File 'lib/active_support/hash_with_indifferent_access.rb', line 157

def to_hash
  Hash.new(default).merge!(self)
end

#to_options! ⇒ Object 



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# File 'lib/active_support/hash_with_indifferent_access.rb', line 154

def to_options!; self end

#update(other_hash) ⇒ Object Also known as: merge!

Updates the instantized hash with values from the second:

hash_1 = HashWithIndifferentAccess.new
hash_1[:key] = "value"

hash_2 = HashWithIndifferentAccess.new
hash_2[:key] = "New Value!"

hash_1.update(hash_2) # => {"key"=>"New Value!"}



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# File 'lib/active_support/hash_with_indifferent_access.rb', line 70

def update(other_hash)
  if other_hash.is_a? HashWithIndifferentAccess
    super(other_hash)
  else
    other_hash.each_pair { |key, value| regular_writer(convert_key(key), convert_value(value)) }
    self
  end
end

#values_at(*indices) ⇒ Object

Returns an array of the values at the specified indices:

hash = HashWithIndifferentAccess.new
hash[:a] = "x"
hash[:b] = "y"
hash.values_at("a", "b") # => ["x", "y"]



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# File 'lib/active_support/hash_with_indifferent_access.rb', line 118

def values_at(*indices)
  indices.collect {|key| self[convert_key(key)]}
end

#with_indifferent_access ⇒ Object 



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# File 'lib/active_support/hash_with_indifferent_access.rb', line 15

def with_indifferent_access
  dup
end