()

a+

a+ - -> b %[stops at -]%

a*b

a->b-

(a->b)-

a-> b * c

(a+ * (b-)+ * d) -> e %[nested variance]%

a->(b->c+)

a->(b->c)+

(a->b+)->c

(a->b+) * d ->c

(a,b->c)

(a+,b) -> c

a*b->c

a+ * b- -> c

(a->b)+ ->c

(a- ->b)+ ->c

a*b->c*d->e

(a*b)->c

(a+ * (b- *c)+ * d) -> e %[nested products]%

(a- * (b+ ->c)- * d-) -> e %[nested products]%

(a- * (b+ ->c)- * d-) -> e %[nested products]%

(a,b) * (c,d) -> (e,f) %[Intersection]%