class Rack::Builder

def self.new_from_string(builder_script, file = "(rackup)")

a Rack::Builder block, returning a Rack application.
Evaluate the given +builder_script+ string in the context of

def self.new_from_string(builder_script, file = "(rackup)")
  # We want to build a variant of TOPLEVEL_BINDING with self as a Rack::Builder instance.
  # We cannot use instance_eval(String) as that would resolve constants differently.
  binding, builder = TOPLEVEL_BINDING.eval('Rack::Builder.new.instance_eval { [binding, self] }')
  eval builder_script, binding, file
  return builder.to_app
end

Class Methods

Instance Methods