class, prototype, meta

Ian Bicking bickiia at earlham.edu
Mon Mar 2 03:45:22 UTC 1998


Tom Morgan writes:
> Here is my try for motivating why assignment is a Big Deal, and a
> metaoperation.
[snipsnipsnip]

I always knew there was something funny about assignment, but I think
as I programmed more that bit of me that was uncomfortable became
numbed.  Now I think I see the problem.

In this context, I kind of like the LOGO way of doing assignment:

MAKE "A :A+1

which makes it clear that "A isn't the same as :A.  Unfortunately,
this construct doesn't seem to make any sense to kids, because you
always put the ":" in front of a variable everywhere except for this
one time.  Then again, MAKE "A :A+1 doesn't make much sense to them in
general, it seems, and it's just an idiom they learn to use.  Maybe
there's a good way of explaining these two oddities at once so it
makes more sense.

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|| Ian Bicking                 |  bickiia at earlham.edu ||
|| drawer #419 Earlham College |  (765) 973-2537      ||
|| Richmond, IN 47374          |                      ||
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