Module: ForwardTo

Defined in:
lib/forward_to.rb,
lib/forward_to/version.rb

Constant Summary collapse

VERSION = 
"0.5.0"

Instance Method Summary collapse

Instance Method Details

#attr_forward(target, *methods) ⇒ Object

Like #forward_to but also add an attr reader method for the member object:

include ForwardTo

class MyArray
  attr_forward :implementation, :empty?, :size, :[]

  def initialize(a = [])
    @implementation = a
  end
end

a = MyArray.new([1, 2, 3])
a.implementation # -> [1, 2, 3]

The target of #attr_reader should be an attribute



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# File 'lib/forward_to.rb', line 71

def attr_forward(target, *methods)
  class_eval("attr_reader :#{target}")
  forward_to(target, *methods)
end

#forward_to(target, *methods) ⇒ Object

Forward methods to member object, arguments can be strings or symbols

Forward to takes the first argument and creates methods for the rest of the arguments that forward their call to the first argument. Example

include ForwardTo

class MyArray
  forward_to :@implementation, :empty?, :size, :[]

  def initialize(a = [])
    @implementation = a
  end
end

a = MyArray.new
a.size # -> 0
a.empty? # -> true
a[0] = 1
a[0] # -> 1
a.implementation # Error - see attr_forward

The target of #forward_to can be an attribute or a member variable



30
 
# File 'lib/forward_to.rb', line 30

def forward_to(target, *methods) = impl_forward_to(target, methods, class_method: false)

#forward_to_class(target, *methods) ⇒ Object

:call-seq:

forward_to_class(class, *methods)
forward_to_class(class-method, *methods)

Create class methods that forwards to class or to the given class method:

module Mod
  def self.module_method() = "other"
end

class Klass
  def self.class_method() = "string"
  forward_to_class :class_method, :size
  forward_to_class Mod, :module_method
end

Klass.size # -> 5
Klass.module_method # -> "other"



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# File 'lib/forward_to.rb', line 51

def forward_to_class(target, *methods) = impl_forward_to(target.to_s, methods, class_method: true)