[plt-scheme] polymorphism of primitive types

From: Yoav Goldberg (yoav.goldberg at gmail.com)
Date: Tue Oct 18 11:17:46 EDT 2005

First of all, I would like to thank you all for the patiance. I do
seem to have many questions.. ;-)

> I believe that you don't want infinite lists but rationale ones, i.e.,
> lists with repeated patterns. These are graphs and you should probably
> just turn them into graphs:
> (define qqh (shared ([qqh (cons quarter (cons quarter (cons half
> qqh)))]) qqh))
> (map (lambda (pitch duration) ...) do-re-mi qqh)
> Have you considered that?
After some playing with it, I found out that:
1/ this is neat.
2/ this doesn't solve my problem - the builtin map doesn't work on graphs.
3/ I prefer streams in this case as they give me much more flexibility
- I can control their sizes, append them, merge them, etc.

(Also: is there a way to increase the font size in the help desk
without affecting DrScheme?)


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