safe_nested_calls

safe_nested_calls

This gem allows you to safely call nested methods on an object, and not worry about whether or not the methods are defined. It is very useful for managing dynamically created objects.

Installation

gem install 'safe_nested_calls'

If you are using Rails, then it will automatically load on server start, but if not, somewhere in your code, put:

require 'safe_nested_calls'

Usage

safe_nested_calls adds two extra methods to Object,

nested_respond_to? and safe_nested_method.

nested_respond_to?

if object.nested_respond_to?(:one, :two, :three)
  

which is equivalent to

if object.respond_to? :one
	if object.one.respond_to? :two
		object.one.two.respond_to? :three

safe_nested_method

This method can call the actual nested method desired, with optional parameters

object.safe_nested_method(:one, :two, :three) => returns object.one.two.three
  

To use parameters, use a hash of :method => args, where args are the method arguments

object.safe_nested_method(:one => 1, :two => [1, 2], :three => [1,2,3])
  

which is equivalent to

object.one(1).two(1,2).three(1,2,3)
  

Parameters

If you need to call of mix of methods with and without parameters, set the arguments for the methods without parameters to :none

object.safe_nested_method(:get => :none, :increment => 4, :save => :none)
  

which is equivalent to

object.get().increment(4).save()