[racket] Saving and restoring many parameters

Perhaps worth pointing out: this PR

   http://bugs.racket-lang.org/query/?cmd=view&pr=12280

is an example of how getting an unexpected parameter setting can lead
to strange behavior.

(This one is a relatively easy one, too; I knew what was going on right away.)

Robby

On Wed, Oct 19, 2011 at 4:47 PM, Neil Toronto <neil.toronto at gmail.com> wrote:
> On 10/19/2011 12:52 PM, Robby Findler wrote:
>>
>> On Wed, Oct 19, 2011 at 12:39 PM, Neil Toronto<neil.toronto at gmail.com>
>>  wrote:
>>>
>>> If I spawn a render thread that inherits the parent thread's parameters,
>>> won't things like current-namespace and current-custodian have the right
>>> values?
>>>
>>> It's starting to look like that is the solution that is the most
>>> maintainable and the least work. And it still allows users to
>>> parameterize
>>> the functions they plot. If something breaks, it's not my fault, because
>>> spawning a thread that waits on a channel for a "draw now!" command, and
>>> then draws on a dc, should just work, right?
>>
>> In either case, it will be equally likely to be your fault.
>>
>> The issue will be if the drawing call back expects parameters to be
>> set in the context in which the actually calback has.
>>
>> Which they might. Maybe.
>
> Gah. You're right.
>
> That's it. I'm going to invent, like, parameter units or something.
>
> Neil T
>