class Hashie::Mash

Mash allows you to create pseudo-objects that have method-like accessors for hash keys. This is useful for such implementations as an API-accessing library that wants to fake robust objects without the overhead of actually doing so. Think of it as OpenStruct with some additional goodies.

A Mash will look at the methods you pass it and perform operations based on the following rules:

Basic Example

mash = Mash.new
mash.name? # => false
mash.name = "Bob"
mash.name # => "Bob"
mash.name? # => true

Hash Conversion Example

hash = {:a => {:b => 23, :d => {:e => "abc"}}, :f => [{:g => 44, :h => 29}, 12]}
mash = Mash.new(hash)
mash.a.b # => 23
mash.a.d.e # => "abc"
mash.f.first.g # => 44
mash.f.last # => 12

Bang Example

mash = Mash.new
mash.author # => nil
mash.author! # => <Mash>

mash = Mash.new
mash.author!.name = "Michael Bleigh"
mash.author # => <Mash name="Michael Bleigh">

Public Class Methods

[](source_hash = nil, default = nil, &blk)
Alias for: new
new(source_hash = nil, default = nil, &blk) click to toggle source

If you pass in an existing hash, it will convert it to a Mash including recursively descending into arrays and hashes, converting them as well.

Calls superclass method
# File lib/hashie/mash.rb, line 53
def initialize(source_hash = nil, default = nil, &blk)
  deep_update(source_hash) if source_hash
  default ? super(default) : super(&blk)
end
Also aliased as: []
subkey_class() click to toggle source
# File lib/hashie/mash.rb, line 61
def subkey_class
  self
end

Public Instance Methods

[](key) { |value| ... } click to toggle source

Retrieves an attribute set in the Mash. Will convert any key passed in to a string before retrieving.

# File lib/hashie/mash.rb, line 79
def [](key)
  value = regular_reader(convert_key(key))
  yield value if block_given?
  value
end
Also aliased as: regular_reader
deep_merge(other_hash) click to toggle source

Performs a #deep_update on a duplicate of the current mash.

# File lib/hashie/mash.rb, line 119
def deep_merge(other_hash)
  dup.deep_update(other_hash)
end
Also aliased as: merge
deep_merge!(other_hash)
Alias for: deep_update
deep_update(other_hash) click to toggle source

Recursively merges this mash with the passed in hash, merging each hash in the hierarchy.

# File lib/hashie/mash.rb, line 126
def deep_update(other_hash)
  other_hash.each_pair do |k,v|
    key = convert_key(k)
    if regular_reader(key).is_a?(Mash) and v.is_a?(::Hash)
      regular_reader(key).deep_update(v)
    else
      regular_writer(key, convert_value(v, true))
    end
  end
  self
end
Also aliased as: deep_merge!, update
delete(key) click to toggle source
Calls superclass method
# File lib/hashie/mash.rb, line 100
def delete(key)
  super(convert_key(key))
end
dup() click to toggle source

Duplicates the current mash as a new mash.

# File lib/hashie/mash.rb, line 106
def dup
  self.class.new(self, self.default)
end
Also aliased as: regular_dup
has_key?(key)
Alias for: key?
include?(key)
Alias for: key?
initializing_reader(key) click to toggle source

This is the bang method reader, it will return a new Mash if there isn't a value already assigned to the key requested.

# File lib/hashie/mash.rb, line 94
def initializing_reader(key)
  ck = convert_key(key)
  regular_writer(ck, self.class.new) unless key?(ck)
  regular_reader(ck)
end
key?(key) click to toggle source
Calls superclass method
# File lib/hashie/mash.rb, line 110
def key?(key)
  super(convert_key(key))
end
Also aliased as: has_key?, include?, member?
member?(key)
Alias for: key?
merge(other_hash)
Alias for: deep_merge
merge!(other_hash)
Alias for: update
method_missing(method_name, *args, &blk) click to toggle source
# File lib/hashie/mash.rb, line 162
def method_missing(method_name, *args, &blk)
  return self.[](method_name, &blk) if key?(method_name)
  match = method_name.to_s.match(/(.*?)([?=!]?)$/)
  case match[2]
  when "="
    self[match[1]] = args.first
  when "?"
    !!self[match[1]]
  when "!"
    initializing_reader(match[1])
  else
    default(method_name, *args, &blk)
  end
end
regular_dup()
Alias for: dup
regular_reader(key)
Alias for: []
respond_to?(method_name, include_private=false) click to toggle source

Will return true if the Mash has had a key set in addition to normal respond_to? functionality.

Calls superclass method
# File lib/hashie/mash.rb, line 157
def respond_to?(method_name, include_private=false)
  return true if key?(method_name)
  super
end
shallow_merge(other_hash) click to toggle source

Performs a #shallow_update on a duplicate of the current mash

# File lib/hashie/mash.rb, line 142
def shallow_merge(other_hash)
  dup.shallow_update(other_hash)
end
shallow_update(other_hash) click to toggle source

Merges (non-recursively) the hash from the argument, changing the receiving hash

# File lib/hashie/mash.rb, line 148
def shallow_update(other_hash)
  other_hash.each_pair do |k,v|
    regular_writer(convert_key(k), convert_value(v, true))
  end
  self
end
update(other_hash)
Also aliased as: merge!
Alias for: deep_update