Module: CoreExtensions::Hash::Parameters

Included in:
Hash
Defined in:
lib/hash_args.rb

Overview

Allows a Hash to more easily be used to pass arguments to methods.

Instance Method Summary collapse

Instance Method Details

#fetch_arg(key, default = nil, opts = {}, &block) ⇒ Object

Works like Hash#fetch with 2 additions. It will optionally treat nil like a missing key (that’s the default). It will also allow the caller to require a parameter or it will raise an exception.



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# File 'lib/hash_args.rb', line 6

def fetch_arg(key, default = nil, opts = {}, &block)
  if opts[:required] == true
    raise ArgumentError, "#{key.to_s.capitalize} required." if not has_key? key
  end

  if not default.nil? or block.nil?
    ret = fetch key, default
  else
    ret = fetch key, &block
  end

  if ret == nil and opts[:ignore_nil] != true
    if opts[:required] == true
      raise ArgumentError, "#{key.to_s.capitalize} required."
    end

    if not block.nil?
      ret = block.call(key)
    else
      ret = default
    end
  end

  if opts[:array] == true and not ret.is_a? Array
    ret = [ret]
  end

  ret
end

#fetch_arg_array(key, default = nil, opts = {}, &block) ⇒ Object 



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# File 'lib/hash_args.rb', line 36

def fetch_arg_array(key, default = nil, opts = {}, &block)
  opts.merge!(:array => true)
  fetch_arg(key, default, opts, &block)
end