# Force the parsing of the module using `modelbuilder`.
	#
	# If the module was already parsed, the existing ASI is returned.
	# Else the source file is loaded, and parsed and some
	#
	# The importation is not done by this
	#
	# REQUIRE: `filepath != null`
	# ENSURE: `modelbuilder.parsed_modules.has(self)`
	fun parse(modelbuilder: ModelBuilder): nullable AModule
	do
		# Already known and loaded? then return it
		var nmodule = modelbuilder.mmodule2nmodule.get_or_null(self)
		if nmodule != null then return nmodule

		var filepath = self.filepath
		assert filepath != null
		# Load it manually
		nmodule = modelbuilder.load_module_ast(filepath)
		if nmodule == null then return null # forward error

		# build the mmodule
		nmodule.mmodule = self
		self.location = nmodule.location
		modelbuilder.build_a_mmodule(mgroup, nmodule)

		modelbuilder.parsed_modules.add self
		return nmodule
	end