can't add variables to instances of built-in classes

[Lawrence D’Oliveiro]

On Wednesday, July 20, 2016 at 6:19:45 PM UTC+12, Chris Angelico wrote:
>
> On Wed, Jul 20, 2016 at 9:58 AM, Lawrence D’Oliveiro wrote:
>>
>> On Wednesday, July 20, 2016 at 9:24:57 AM UTC+12, bream... at gmail.com wrote:
>>>
>>> On Tuesday, July 19, 2016 at 3:54:12 AM UTC+1, Lawrence D’Oliveiro wrote:
>>>>
>>>> On Tuesday, July 19, 2016 at 11:12:52 AM UTC+12, bream... at gmail.com
>>>> wrote:
>>>>>
>>>>> On Monday, July 18, 2016 at 10:48:15 PM UTC+1, Lawrence D’Oliveiro
>>>>> wrote:
>>>>>>
>>>>>> <https://github.com/ldo/qahirah>
>>>>>> When you have lots of read/write properties, I find __slots__ to be a
>>>>>> good idea.
>>>>>
>>>>> Please explain why, thank you.
>>>>
>>>> I was trying something like
>>>>
>>>>     ctx.dashes = ((0.1, 0.03, 0.03, 0.03), 0)
>>>>
>>>> and wondering why it wasn’t working...
>>>
>>> This makes no sense to me at all.  You appear to be trying to create a
>>> tuple, which contains a tuple and an integer.  You then say it doesn't
>>> work, but imply that using __slots__ fixes the problem.  So please explain
>>> exactly what you were trying to achieve, the exact error you got, with the
>>> complete traceback, and how using __slots__ fixed the problem.
>>
>> No traceback. The lines were simply coming out solid, instead of dashed.
> 
> And __slots__ fixed the problem how, exactly?

The Context attribute that controls the dash settings is called “dash”, not “dashes”.

> This sounds like the sort of cargo cult debugging that I'd expect of PHP
> programmers ("I put addslashes around everything and now it works, so in
> future I'll use addslashes everywhere"), but around here, we're better than
> that.

OK, boss.