# Build `mexpect` if is not exist and return it
	private fun build_expect: MExpect
	do
		var m_mexpect = self.mexpect
		# build a new `MExpect` contract
		if m_mexpect == null then m_mexpect = new MExpect(intro_mclassdef, "_expect_{name}", intro_mclassdef.location, public_visibility)
		self.mexpect = m_mexpect
		return m_mexpect
	end