Class: Oj::EasyHash

Inherits:
Hash
  • Object
show all
Defined in:
lib/oj/easy_hash.rb

Overview

A Hash subclass that normalizes the hash keys to allow lookup by the key.to_s or key.to_sym. It also supports looking up hash values by methods that match the keys.

Instance Method Summary collapse

Dynamic Method Handling

This class handles dynamic methods through the method_missing method

#method_missing(m, *args, &block) ⇒ Boolean

Handles requests for Hash values. Others cause an Exception to be raised.

Parameters:

  • m (Symbol|String) —

    method symbol

Returns:

  • (Boolean) —

    the value of the specified instance variable.

Raises:

  • (ArgumentError) —

    if an argument is given. Zero arguments expected.

  • (NoMethodError) —

    if the instance variable is not defined.



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# File 'lib/oj/easy_hash.rb', line 33

def method_missing(m, *args, &block)
  if m.to_s.end_with?('=')
    raise ArgumentError.new("wrong number of arguments (#{args.size} for 1 with #{m}) to method #{m}") if args.nil? or 1 != args.length

    m = m[0..-2]
    return store(m.to_s, args[0]) if has_key?(m.to_s)
    return store(m.to_sym, args[0]) if has_key?(m.to_sym)

    return store(m, args[0])
  else
    raise ArgumentError.new("wrong number of arguments (#{args.size} for 0 with #{m}) to method #{m}") unless args.nil? or args.empty?
    return fetch(m, nil) if has_key?(m)
    return fetch(m.to_s, nil) if has_key?(m.to_s)
    return fetch(m.to_sym, nil) if has_key?(m.to_sym)
  end
  raise NoMethodError.new("undefined method #{m}", m)
end

Instance Method Details

#[](key) ⇒ Object 



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# File 'lib/oj/easy_hash.rb', line 21

def [](key)
  return fetch(key, nil) if has_key?(key)
  return fetch(key.to_s, nil) if has_key?(key.to_s)

  fetch(key.to_sym, nil)
end

#respond_to?(m, include_all = false) ⇒ Boolean

Replaces the Object.respond_to?() method.

Parameters:

  • m (Symbol) —

    method symbol

  • include_all (Boolean) (defaults to: false) —

    whether to include private and protected methods in the search

Returns:

  • (Boolean) —

    true for any method that matches an instance variable reader, otherwise false.



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# File 'lib/oj/easy_hash.rb', line 13

def respond_to?(m, include_all = false)
  return true if super
  return true if has_key?(m)
  return true if has_key?(m.to_s)

  has_key?(m.to_sym)
end