1
2a = bad
3b = news
4x = $(let a b,   1   2   ,+$a+$b+)
5y = $(let a,   1  2   ,+$a+)
6z = $(let a b,  1   ,+$a+$b+)
7all:;@echo 'a=,$a,' 'b=,$b,' 'x=,$x,' 'y=,$y,' 'z=,$z,'