Sep 29, 2003
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- More on pointer problems
	- dangling references
	- garbage

- Solutions for dangling references
	- 1. do not give the programmer access to pointers!
	- 2. tombstones
	- 3. lock-and-key approahc

- Solutions for garbage
	- 1. do not give the programmer access to pointers!
	- 2. reference counting
	- 3. garbage collection

- onto next Chapter: expressions

- Key ideas in expression evaluation
	- precedence
	- associativity
	- order of writing expressions
		- infix, prefix, postfix
	- order of evaluating expressions
		- applicative order (eager)
		- normal order (delayed)