[plt-scheme] cutting and pasting snips

From: Robby Findler (robby at cs.uchicago.edu)
Date: Wed Oct 18 08:55:53 EDT 2006

At a high-level, perhaps it is time to reconsider what the value of  
examples & tests are? If the function is easier to work out than the  
examples, I submit that we don't gain anything by making them write  
out the examples. On the tests side, tests generated by running a  
function are still valuable -- so valuable that there is even a  
special name for them (regression tests). They help make sure that  
there are no unintended changes as the program evolves.

Anyways, all this suggests (to me) that when punishing students for  
such copy/paste hijinks isn't working, perhaps the solution is to  
reconsider the goals of the lesson.

More specific, drscheme-centric comments below.

On Oct 18, 2006, at 6:07 AM, Prabhakar Ragde wrote:

> Robby Findler wrote:
>
>> Seems easy enough to throw wxme-to-text into your script that does  
>> the
>> printing .... seems like it would work for your purposes. Why not  
>> do it?
>
> I probably should, but see below. (And thanks for the drs-to-ps  
> script, which I will study and adapt.)

Don't spend too much time on it; it isn't the best way to write such  
a script. If you need changes, you might just contact me instead,  
since it uses strange corners of drscheme to do things.

>> Disabling it globally seems bad. If you wanted to disable it for your
>> course, that's fine (and I gave you some tips in my last message  
>> -- but
>> I'm loathe to actually post that code, as you might guess!). My
>> students use images in the first assignment, and I think that  
>> probably
>> this is a good way to go for many classrooms. So, you can see I'm
>> hesitant to disable it even in the teaching languages.
>
> My first assignment also uses images (and Kathi's fabric  
> teachpack). But it's still not necessary to cut them out of the  
> Interactions window and paste them into Definitions, and in any  
> case I am not talking about images. I am talking about numerical  
> results. I ask them to do something like compute taxes in a multi- 
> bracket system, and they create their examples and tests by running  
> their code, getting numbers in Definitions, cutting them out, and  
> pasting them into an example-comment or a Boolean test expression.  
> Except taxes have decimal places, typically, and what they paste is  
> not a piece of simple text, but a snip.

You want to disallow cutting and pasting all together then? When they  
start typing them in, reading them from the interactions? Maybe  
disallow the ability to see the interactions window? Oh, but they  
might write them down on paper before switching views.
You see where this is going; clearly the right solution is to abandon  
drscheme entirely; just make them do the homework with paper &  
pencil ....

;)

> What is the utility of permitting a student to cut a snip  
> representing a rational, as opposed to a textual representation of  
> a number, out of the Interactions window?

Simply put: it doesn't hurt. In a few more words: why should we keep  
the students from using their natural notations simply so we can  
continue to use Emacs / perl (or whatever)?

Robby



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