class Hashery::OrderedHash

OrderedHash is a simple ordered hash implmentation, for users of Ruby 1.8.7 or less.

NOTE: As of Ruby 1.9+ this class is not needed, since Ruby 1.9's standard Hash tracks inseration order.

This implementation derives from the same class in ActiveSupport library.

Public Class Methods

[](*args) click to toggle source
# File lib/hashery/ordered_hash.rb, line 36
def self.[](*args)
  ordered_hash = new

  if (args.length == 1 && args.first.is_a?(Array))
    args.first.each do |key_value_pair|
      next unless (key_value_pair.is_a?(Array))
      ordered_hash[key_value_pair[0]] = key_value_pair[1]
    end

    return ordered_hash
  end

  unless (args.size % 2 == 0)
    raise ArgumentError.new("odd number of arguments for Hash")
  end

  args.each_with_index do |val, ind|
    next if (ind % 2 != 0)
    ordered_hash[val] = args[ind + 1]
  end

  ordered_hash
end
new(*args, &block) click to toggle source
Calls superclass method
# File lib/hashery/ordered_hash.rb, line 31
def initialize(*args, &block)
  super
  @keys = []
end

Public Instance Methods

[]=(key, value) click to toggle source
Calls superclass method
# File lib/hashery/ordered_hash.rb, line 65
def []=(key, value)
  @keys << key unless key?(key)
  super(key, value)
end
clear() click to toggle source
Calls superclass method
# File lib/hashery/ordered_hash.rb, line 124
def clear
  super
  @keys.clear
  self
end
delete(key) click to toggle source
Calls superclass method
# File lib/hashery/ordered_hash.rb, line 70
def delete(key)
  if has_key? key
    index = @keys.index(key)
    @keys.delete_at(index)
  end
  super(key)
end
delete_if() click to toggle source
Calls superclass method
# File lib/hashery/ordered_hash.rb, line 78
def delete_if
  super
  sync_keys!
  self
end
each() { |key, self| ... } click to toggle source
# File lib/hashery/ordered_hash.rb, line 118
def each
  @keys.each{ |key| yield(key, self[key]) }
end
each_key() { |key| ... } click to toggle source
# File lib/hashery/ordered_hash.rb, line 110
def each_key
  @keys.each{ |key| yield(key) }
end
each_value() { |self| ... } click to toggle source
# File lib/hashery/ordered_hash.rb, line 114
def each_value
  @keys.each{ |key| yield(self[key]) }
end
initialize_copy(other) click to toggle source
Calls superclass method
# File lib/hashery/ordered_hash.rb, line 60
def initialize_copy(other)
  super(other)
  @keys = other.keys
end
inspect() click to toggle source
# File lib/hashery/ordered_hash.rb, line 153
def inspect
  "#<OrderedHash #{super}>"
end
keys() click to toggle source
# File lib/hashery/ordered_hash.rb, line 94
def keys
  @keys.dup
end
merge(other_hash) click to toggle source
# File lib/hashery/ordered_hash.rb, line 141
def merge(other_hash)
  dup.merge!(other_hash)
end
merge!(other_hash) click to toggle source
# File lib/hashery/ordered_hash.rb, line 136
def merge!(other_hash)
  other_hash.each{ |k,v| self[k] = v }
  self
end
reject(&block) click to toggle source
# File lib/hashery/ordered_hash.rb, line 90
def reject(&block)
  dup.reject!(&block)
end
reject!() click to toggle source
Calls superclass method
# File lib/hashery/ordered_hash.rb, line 84
def reject!
  super
  sync_keys!
  self
end
replace(other) click to toggle source

When replacing with another hash, the initial order of our keys must come from the other hash, ordered or not.

Calls superclass method
# File lib/hashery/ordered_hash.rb, line 147
def replace(other)
  super
  @keys = other.keys
  self
end
shift() click to toggle source
# File lib/hashery/ordered_hash.rb, line 130
def shift
  k = @keys.first
  v = delete(k)
  [k, v]
end
sync_keys!() click to toggle source
# File lib/hashery/ordered_hash.rb, line 159
def sync_keys!
  @keys.delete_if{ |k| !key?(k) }
end
to_a() click to toggle source
# File lib/hashery/ordered_hash.rb, line 106
def to_a
  @keys.map{ |key| [ key, self[key] ] }
end
to_hash() click to toggle source
# File lib/hashery/ordered_hash.rb, line 102
def to_hash
  self
end
to_yaml(opts = {}) click to toggle source
# File lib/hashery/ordered_hash.rb, line 18
def to_yaml(opts = {})
  YAML.quick_emit(self, opts) do |out|
    out.seq(taguri, to_yaml_style) do |seq|
      each do |k, v|
        seq.add(k => v)
      end
    end
  end
end
to_yaml_type() click to toggle source
# File lib/hashery/ordered_hash.rb, line 14
def to_yaml_type
  "!tag:yaml.org,2002:omap"
end
values() click to toggle source
# File lib/hashery/ordered_hash.rb, line 98
def values
  @keys.collect{ |key| self[key] }
end