Main module bitt
	%set use_routine_names = true
	use textio
	Declare
		pa 	is packed array [1..16] of 4 bit integer
		a	is array [1..16] of 4 bit integer
		pack_4 	: static pa
		pack_a	: static pa
		easy_4 	: static a 
		easy_a 	: static a 
		pack_tab = table pa (-8,-7,-6,-5,-4,-3,-2,-1,
				      0, 1, 2, 3, 4, 5, 6, 7 )
		easy_tab = table a  (-8,-7,-6,-5,-4,-3,-2,-1,
				      0, 1, 2, 3, 4, 5, 6, 7 )
		v = 3
		i	: static integer initially 2
		j 	: static integer initially 3
		error	: boolean initially false	
	enddeclare
	
	pack_4[i] := v
	pack_4[j] := -v
	easy_4[i] := v
	easy_4[j] := -v
	assert easy_4[i] = v
	assert easy_4[j] = -v

	if pack_4[i] = v do
	otherwise
		error := true
		tty_line("read of single value failed")
	endif
	if pack_4[j] = -v do
	otherwise
		error := true
		tty_line("read of single negative value failed")
	endif

	for i := -8 to 7 do
		pack_4[i+9] := i
		pack_a[i+9]:= i
		easy_4[i+9] := i
		easy_a[i+9] := i
	endfor

	assert easy_4 = easy_tab
	assert easy_4 = easy_a

	if pack_4 = pack_tab do
	otherwise
		error := true
		tty_line("compare of constant with loop set array failed")
	endif

	if pack_4 = pack_a do
	otherwise
		error := true
		tty_line("compare of two loop set arrays failed")
	endif

	for i := -8 to 7 do
		assert easy_4[i+9] = i
		if pack_4[i+9] = i do
		otherwise
			error := true
			out_string(tty,"comparison fails at i=")
			out_integer(tty,i)
			out_record(tty)
		endif
	endfor
	assert not error
endmodule