Syntax Analysis

Recursive Descent Predictive Parsing (RDPP)
(ASU Ch 2.4)
• Define the (disjoint) sets “first” for each NT on RHS of P
– first() = {integer, char, num}
– first(^id) = {^}
– first(array …) = {array}
• PP (predictive Parser) requires
– procedure for every NT - takes action based on first(a) for a
on the RHS of a production P (using lookahead)
– RHS of P
• NT => call to corresponding procedure
• T => match expected token with actual token (no match =>
error) and get next token
– left recursion may have to be removed from the grammar
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14/10/2014 DFR - CC - Syntax Analysis