[plt-scheme] error in student languages

From: Stephen Bloch (sbloch at adelphi.edu)
Date: Thu Dec 31 13:30:29 EST 2009

On Dec 31, 2009, at 1:05 PM, Matthew Flatt wrote:

> The situation with `error' is indeed in flux and confusing.
> 
> Here's a recap:
> 
> Version 4.2.2 and before: `error' in ISL (and other HtDP languages)
>   expected 2 arguments: symbol and string.
> 
> Version 4.2.3: `error' changed to expect a single string argument.
> 
> Version 4.2.3.x (SVN and nightly builds): `error' takes any number of
>   arguments; it isn't currently documented correctly.

And if the first one is a symbol, it puts a colon after it?


I don't want to be a pain; I'm just trying to complete a beta-release of the textbook today, and to send a complete draft to the publisher next month, so it would be nice if this were stabilized by then.

On a related note, is there an ETA on making universe compatible with 2htdp/image?  (If it's soon, I need to rewrite a bunch of things that way; if not, I have less rewriting to do.)


Stephen Bloch
sbloch at adelphi.edu





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