Recursive Descent Example 1 S  a S b S  b S a S  x All “symbols” starting with uppercase are non-terminals, all other symbols are terminals

Recursive Descent Example 2 S  F F  ID ( ARGS ) ARGS  ARG , ARGS ARGS  ARG ARG  ID | IntLit ID  x | y | z IntLit  0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9

Recursive Descent Example 3 S  if ( ID RelOP ID ) A A  A A A  ID = ID A  ID = IntLit ID  x | y | z IntLit  0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 RelOp  < | > | == | != | <= | >=

Recursive Descent Example 3a S  if ( ID RelOP ID ) A A  B A A  ε // empty string B  LID = ID LID  x | y | z ID  LID | IntLit IntLit  0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 RelOp  < | > | == | != | <= | >=