Symbols

Symbol	Context	Usage
*	*<Class>	create instance
	restriction	select all instances
	projection	select all attributes
	*I<n> projection	project all identifer attrs
	computation	type specific op (multiply)
=	all	scalar value assignment
#=	all	table value assignment
#.=	all	assign at most one tuple
.=	all	assign at most one instance
..=	all	assign 0, 1 or many instances
0	restriction	select no instances
1	restriction	select at most one instance
*In	projection	project all In attributes
-attr	projection	select all but attr
~	path	repeated hopping
->	all	send signal
@	all	time of signal delivery
=>	all	asynch bridge
:	restriction	equals, matches
:	projection	rank delimiter
;	table definition	row delimiter
!=, ==, <, >, <=, >=	all	comparison