[racket] Functional mutators (was: syntax, differently)

A couple of stylistic questions that I just have to get off my chest:

1. Is there a reason that mutators don't start with the struct name
like all the other functions introduced by "define-struct"? Especially
now that "make-struct" defaults to just "struct" in #lang racket,
would it make sense to have "struct-set-field" and "struct-set-field!"
instead of "set-struct-field" and "set-struct-field!" so that all the
functions introduced by struct and define-struct would appear together
in an alphabetical list?

2. Just as a personal peeve, I find it confusing that we use dash to
separate words in identifier names *and* to separate names of structs
and fields in selectors. I've started using a dot to separate the type
of structure from the function name to avoid ambiguity. For example,
suppose I'm implementing the (very fun) card game "Set." I might have
a set-world struct that I've defined. So then I get "set-world-cards".
You see the problem. If instead I were to write "set-world.cards",
it's pretty clear that I'm calling the selector for the "cards" field
on the structure "set-world".

The separator character clearly doesn't need to be a dot--underscore
is another possibility--and I'm sure that changing the convention
would be a nightmare throughout the code, but is it worth considering
such a change for HtDP/2e?

Todd

On Sun, Aug 1, 2010 at 6:42 PM, Matthias Felleisen <matthias at ccs.neu.edu> wrote:
>
> So when define-struct introduces functional mutators as planned for a while now, and this program looks like this:
>
>  (cond
>   [(mouse-in? 248 x 424 570 y 649) (set-world-background blah)]
> ...
>
> Matthew will be happy?
>
>
>
> On Aug 1, 2010, at 6:14 PM, Todd O'Bryan wrote:
>
>> You'd create the new world and set field values using mutators.
>>
>> So
>>
>> if (x > 248 && x < 424 && y > 570 && y < 649) {
>>    SState newState = new SState();
>>    newState.setBackground(blah);
>>    newState.setButton(blah2);
>>    ...
>> }
>>
>> On Sun, Aug 1, 2010 at 5:22 PM, Richard Cleis <rcleis at mac.com> wrote:
>>> [snip]
>>>
>>> I was trying to emphasize that it may be harder to students to keep their
>>> code neater compared to some other languages which usually have code that
>>> rarely exceed 1 line.
>>> Example:
>>> Racket using the universe teachpack:
>>> (define (s-mouse-engine s x y event)
>>>   (cond
>>>     [(and
>>>       (and (> x 248)           (< x 424))
>>>       (and (> y 570)           (< y 649)))
>>>         (make-S-STATE
>>>          (get-s-background s)                ;;I have made methods here to
>>> reduce length, but other wise it would be longer.
>>>          (make-button
>>>           (s-mouse-engine-worker1 event "button-img")
>>>           (get-s-button-x s)                   ;;I have made methods here to
>>> reduce length, but other wise it would be longer.
>>>           (get-s-button-y s)                   ;;I have made methods here to
>>> reduce length, but other wise it would be longer.
>>>           (s-mouse-engine-worker1 event "button-initiate")))]
>>>
>>> How would you write that in another language that rarely exceeds one line?
>>> rac
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