How to eliminate left recursion for the following grammar?
E := EE+|EE-|id
Using the common procedure:
A := Aa|b
translates to:
A := b|A'
A' := ϵ| Aa
Applying this to the original grammar we get:
A = E, a = (E+|E-) and b = id
Therefore:
E := id|E'
E' := ϵ|E(E+|E-)
But this grammar seems incorrect because
ϵE+ -> ϵ id +
would be valid but that is an incorrect postfix expression.