- Notes from 11/18/02

- timing utils
	- runtime - time actually spent executing instructions while not looking for memory
	- gc-time - time spent dealing with memory (garbage collection)
	- realtime - wall-clock time (different from sum b/c of other processes)

	- usually interested in run+gc time
	- however, gc will increase as the heap gets 'worse'
	- ie, gc time is dependent on state before you start, unlike runtime

- iteration/recursion and enviroment frames
	- recursion adds frames in a chain, logically
	- each function call adds a new one
	- for iteration, previous frames will be thrown away once you reach the last one
	- so you can just throw them away immediatly rather than waiting
	- overwrite the old frame with the current one
	- efficient

- note on timing stream implementations
	- streams get cached!
	- ie doing (stream-head stream 500) twice in a row will give 0 time the 2nd time
	- replaces forced promises with values
	- turns into a long list of values with a promise at the end
	- redefine may clear the cache if you want to re-time
	- supposedly no easy function though

- all you need is lambda!
	- nifty!
	- functions of one arg - all you need, since more than one can be simulated this way
	- look at demo of cons, car, cdr, and the start of integers