[racket] color does not match like other structs

On Aug 29, 2012, at 2:08 PM, Danny Yoo wrote:

> I think part of what was interfering with what you were doing earlier
> is that the 'color' structure isn't exposed as a structure in
> 2htdp/image, but instead is exposed as a HTDP-level primitive.

Which begs the question: why did matching on "make-posn" work?  Shouldn't posn be exposed in the same way as color?

Or is this something to do with make-color, which does error-checking and has an optional argument with a default value and all sorts of complicated stuff that make-posn doesn't do?



Stephen Bloch
sbloch at adelphi.edu