Screen in pic
-------------

	+

	^
	|
	up

	-

	^    (x,y)
	|
	|
	|
	o---> - right -> +

	(0,0)

Macros 
------

	==
	define name {
		replacement
	}

	`name' gets replaced per `replacement', each time it appears

	if replacement contains $1,$2, ..., these are replaced for
	given arguments

	calls: 
		name			no args
		name(arg1, arg2, ,,,)	with args ($1 is replaced by arg1, etc)

	empty args, are replaced by null: 
		define f { $1 $2 }
		f() -> $1 and $2 are nulls

	==
	undef name

	undefined `name', i.e `name' will stand for itself from now on


==
Carlos Duarte, 981015/981026