Jack Nagel 2503cedf2c Object#instance_exec for Ruby 1.8.6
Not thread safe! But I don't think we care.

We want to evaluate the env DSL block in the context of ENV for asthetic
reasons, but we also want access to methods on the requirement instance.
We can use #instance_exec to pass the requirement itself into the block:

  class Foo < Requirement
    env do |req|
      append 'PATH', req.some_path
    end

    def some_path
      which 'something'
    end
  end

Also add a simplified version of Object#instance_exec for Ruby 1.8.6.
2013-01-21 17:24:11 -06:00

16 lines
422 B
Ruby

class Object
def instance_exec(*args, &block)
method_name = :__temp_instance_exec_method
singleton_class = (class << self; self; end)
singleton_class.class_eval do
define_method(method_name, &block)
end
send(method_name, *args)
ensure
singleton_class.class_eval do
remove_method(method_name) if method_defined?(method_name)
end
end unless method_defined?(:instance_exec)
end