[plt-dev] 2htdp/image: Where oh where have my pinholes gone?

From: Matthias Felleisen (matthias at ccs.neu.edu)
Date: Wed Jan 13 10:23:06 EST 2010

To clarify:

Say you run a test like this:

  (check-expect (image-producing-function 1 "true") expression-that- 

and it fails. Naturally, you do this in the REPL:

 > (image-producing-function 1 "true")
 > expression-that-creates-expected-image

;; you're confused and you run an equality check:

 > (equal? (image-producing-function 1 "true") expression-that-creates- 

Now you're really confused, and you're angry, because clearly there  
must be a bug in this damn software that your instructor imposes on  
you even though everyone knows that in a first course you should learn  
Java or at least C++, well may be Basic. So you stomp into your  
professors office and yell. At that point he pulls out a standard  
function -- not in the released library mind you -- and shows you're  
just not thinking properly:

 > (image+pinhole (image-producing-function 1 "true"))
 > (image+pinhole expression-that-creates-expected-image)

So now that you have been shown off again, you know what's going on.  
This guy is just trying to humiliate you. You are going to write a bad  
eval for him and you're going to bad-mouth this stupid software  
wherever you can.

;; ---

The above account is fictional. All possible connections between the  
characters and real-life people is coincidence.

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