Recursive Descent Parser

Question

Does RDP require back tracking ?

I am asking this because I have read that if RDP doesn't require back tracking then it is a predictive parser(LL(1))!! 

A predictive parser is a recursive descent parser that does not require backtracking. Predictive parsing is possible only for the class of LL(k) grammars 

(  https://en.wikipedia.org/wiki/Recursive_descent_parser  )

Does it mean that the RDP requires BT

Answer 1

Recursive Descent Parser can have backtracking. It is the most primitive level top down approach of parsing. It usually does backtracking and applies brute force to evaluate the grammar. Moreover, we have something called Predictive Parser, which is a more sophisticated way of using top down parsing approach, which doesn't need backtracking. LL(1) is one of the kind of predictive parser.

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