Question

I want to extend the Proc class so that its constructor can also take a hash of arguments with will be converted into methods with some meta programming construct. Something to the effect of:

p = Proc.new(this: 100, that: 200, yes: 1, no: 2) { |arg| arg.even? }
p.call(1) # => false
p.this # => 100
p.yes # => 1

I want to know the ruby way of doing something like this.

Answer 1

class Proc
  def initialize h; @h = h end
  def method_missing k; @h[k] end
  def respond_to_missing?; true end
end

p = Proc.new(this: 100, that: 200, yes: 1, no: 2) { |arg| arg.even? }
p.call(1) # => false
p.this # => 100
p.yes # => 1