Transforming

• Transform in stages, for example the first stage might eliminate left recursion, so

  • exp = term | exp + term OP | exp - term OP

• becomes

  • exp = term exp1
  • exp1 = + term OP exp1 | - term OP exp1

• or

  • exp = term ( + term OP | - term OP )*

• Each transformation comes with an explanation

• Originally, each rule is deterministic only if you give it a start and end point, now you only need a start point and a longest parse convention