CS 228 meeting -*- Outline -*-

* introduction to abstraction section (HR introduction)

	Q: what is abstraction? What is it good for?

		separation of what from how, contract, suppress details,
			allows improvements to implementation without
			retraining users

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     ABSTRACTION

The idea:

        user (client)

    === specification ===

        implementation
---------------------------
	The specification is a contract.
		critical idea

	This is the theory, but in practice, some performance details
		are not very well hidden; it's a research issue...

	essential to abstraction is the ability to give something a name,
		to parameterize it, and to specify it's behavior

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KIND OF ABSTRACTION \ HIDES

	functional    algorithm

	      data    rep + algorithms

	    control   flow details
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	in general, separate behavior from implementation of it
		(separation of concerns, so don't keep everything in our heads)