module FirstOf

Constants

VERSION

Public Instance Methods

first_of(*args) click to toggle source

Should take arguments: first_of(:symbol1, :symbol2) # will return first respond to and present first_of([:symbol1, :symbol2]) # will return value if try_chain(:symbol1, :symbol2) present first_of(1 => :symbol1, 2 => :symbol2) # will prioritize trying by key and return first present first_of(1 => :symbol1, 2 => lambda { _call }) # will prioritize and only execute callable if first not present first_of(1 => [:symbol1, :symbol2], 2 => -> { _call }) # will prioritize and execute try_chain on first and call 2nd if first not present first_of(1 => :symbol1, 2 => 4) # will prioritize and return value (4) if first not present first_of(lambda { _call }, 1 => :symbol1, 2 => :symbol2)

# File lib/first_of.rb, line 18
def first_of(*args)
  return _first_of(*args, :try_chain, :proxy_try_chain)
end

first_of!(*args) click to toggle source

# File lib/first_of.rb, line 22
def first_of!(*args)
  return _first_of(*args, :try_chain!, :proxy_try_chain!)
end

Private Instance Methods

_extract_from_message_chain(methods_or_value, try_method = :try_chain, proxy_try_method = :proxy_try_chain) click to toggle source

# File lib/first_of.rb, line 28
def _extract_from_message_chain(methods_or_value, try_method = :try_chain, proxy_try_method = :proxy_try_chain)
  case methods_or_value
  when Symbol, Array then
    if self.respond_to?(:try_chain)
      self.__send__(try_method, *methods_or_value)
    else
      ::TryChain.__send__(proxy_try_method, self, *methods_or_value)
    end
  else
    methods_or_value
  end
end

_first_of(*args, try_method, proxy_try_method) click to toggle source

# File lib/first_of.rb, line 41
def _first_of(*args, try_method, proxy_try_method)
  extract_hash = args.extract_options!        

  # Don't care if the hash is empty or not because of #each call
  sorted_keys = extract_hash.keys.sort
  sorted_keys.each do |key|
    args << extract_hash[key]
  end

  args.each do |argument|
    if argument.respond_to?(:call)
      value = argument.call
    else
      value = _extract_from_message_chain(argument, try_method, proxy_try_method)
    end

    return value if _valid_value?(value) # return value if found
  end

  return nil
end

_valid_value?(value) click to toggle source

# File lib/first_of.rb, line 63
def _valid_value?(value)
  value.present? || [true, false].include?(value)
end