# Retrieve the associated AST node of a mpropertydef.
	# This method is used to associate model entity with syntactic entities.
	#
	# If the property definition is not associated with a node, returns `null`.
	fun mpropdef2node(mpropdef: MPropDef): nullable ANode
	do
		var res
		res = mpropdef2npropdef.get_or_null(mpropdef)
		if res != null then
			# Run the phases on it
			toolcontext.run_phases_on_npropdef(res)
			return res
		end
		# Fall back to the class node if any.
		res = mclassdef2nclassdef.get_or_null(mpropdef.mclassdef)
		if res != null then return res
		return null
	end