Sep 08, 2003
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- Move onto Chap 4
	- a sneak peek into compiler world

- Lexical analysis
	- recognizing tokens, lexemes
	- model based on finite state machines
	
- Example of coding up a lexical analyzer
	- distinguishing between numbers and identifiers

- Syntax analysis
	- building up a parse tree
	- or just simply checking for validity

- Main types of parsers
	- top-down: easy to code up
	- bottom-up: safe

- Design of a top-down parser
	- for <sentence> grammar
	- assumes Token global variable has the next
	  token to be analyzed
		- every procedure/function that consumes
		  this token must return the favor, by
		  calling getNextToken()

- Caveats to watch out for
	- left recursion
		- <exp> -> <exp> + <term>
		- get rid of it!
	- optional arguments
		- <ifstmt> ->  if .. then .. | if .. then .. else
		- left factor the grammar!
	- right recursion causes no problem
		- why?