module RSpec::Core::MemoizedHelpers::ClassMethods

def let(name, &block)

Other tags:
    Note: - Because `let` is designed to create state that is reset between
    Note: - `let` can be configured to be threadsafe or not.
    Note: - `let` _can_ enhance readability when used sparingly (1,2, or 
def let(name, &block)
  # We have to pass the block directly to `define_method` to
  # allow it to use method constructs like `super` and `return`.
  raise "#let or #subject called without a block" if block.nil?
  raise(
    "#let or #subject called with a reserved name #initialize"
  ) if :initialize == name
  MemoizedHelpers.module_for(self).__send__(:define_method, name, &block)
  # Apply the memoization. The method has been defined in an ancestor
  # module so we can use `super` here to get the value.
  if block.arity == 1
    define_method(name) { __memoized.fetch_or_store(name) { super(RSpec.current_example, &nil) } }
  else
    define_method(name) { __memoized.fetch_or_store(name) { super(&nil) } }
  end
end