Comments on: Algebra of Programming: Chapter 1 Section 2

By: John Bender

John Bender — Fri, 08 Jul 2011 05:30:27 +0000

DCWhatthe,

Long time waiting for this reply but its not possible to purchase the eBook. Though there are places on the internet you can download it from ;)

By: DCWhatthe

DCWhatthe — Sun, 17 Apr 2011 23:32:24 +0000

Is it possible to purchase a PDF or other ebook version of Algebra of Programming?

By: Oscar

Oscar — Tue, 03 Nov 2009 20:07:30 +0000

awesome – but i’m still a little confused by foldn:

what’s is its type definition?

also which compiler are (were) you using? it doesn’t seem to be built into HUGS

also i recomend bird if you get stuck, and hutton if you get stuck with him…

By: CL

CL — Mon, 05 Oct 2009 18:48:53 +0000

In order to figure out the squares, first consider: id n = foldn Zero Successor n. Which we can rewrite as: id n = foldn 0 (1 ) n. In order to square a number we want to have n copies of n, so for each of the n many (1 ) in n, we use (n ) instead:

square n = foldn Zero (plus n) n

By: John Bender

John Bender — Sun, 13 Sep 2009 23:48:57 +0000

@wren

The solution provided, see the link above in the article, involved using a selection function composed with foldn and required something more complex than your own solution.

thank you though for the insight.

By: wren ng thornton

wren ng thornton — Sun, 13 Sep 2009 22:32:46 +0000

square n = foldn Zero (plus n) n

By: John Bender

John Bender — Sun, 13 Sep 2009 16:02:41 +0000

@Sean

I think if you order from the third party merchant on the site, its printed for you. There are no more copies in circulation.

By: Sean

Sean — Sun, 13 Sep 2009 14:38:37 +0000

How did you do the order the print-on-demand copy?