. and : proc chaining error

var/SomeDatum1/datum1
proc/GetSomething1()
	return datum1

SomeDatum1
	proc/DoSomething(SomeDatum2/datum2)
		world << datum2.name //Should output "Test"

SomeDatum2
	var tmp
		name = "Test"

	proc/Self()
		return src
mob
	Login()
		. = ..()

		datum1 = new
		var/SomeDatum2/datum2 = new

		GetSomething1().DoSomething(datum2.Self()) 	//This method of chaining causes an error where datum2 is trying to call DoSomething()
													//It should be datum1 calling DoSomething()