Fwd: A typing question

[Paulo da Silva]

Às 02:32 de 30/10/22, dn escreveu:
> On 30/10/2022 11.59, Paulo da Silva wrote:
>>> Solution (below) will not work if the mention of Foos in GLOBALS is a 
>>> forward-reference. Either move GLOBALS to suit, or surround "Foos" 
>>> with quotes.
>> This is the problem for me. So far, without typing, I used to have 
>> some config and globals classes, mostly to just group definitions an 
>> make the program more readable. A matter of taste and style.
> 
> Agreed, a good practice.
Thank you.
> 
> 
>> Now, "typing" is breaking this, mostly because of this forward 
>> reference issue.
> 
> As a first step, use the quotation-marks to indicate that such will be 
> defined later in the code:-
> 
>> class GLOBALS:
>>     Foos: Optional[Foos]=None 
> 
> class GLOBALS:
>      Foos: Optional["Foos"]=None
> 
> 
> Later, as gather (typing) expertise, can become more sophisticated, 
> as-and-when...
> 
> 
>> The funny thing is that if I replace foos by Foos it works because it 
>> gets known by the initial initialization :-) !
> 
> Is the objective to write (good) code, or merely to satisfy the 
> type-checker?
> 
> Something that is misleading is not going to be appreciated by others 
> (including the +6-months you), eg
> 
> a = a + 1   # decrement total
> 
> Typing is not compulsory, and has been designed so that we can implement 
> it a bit at a time, eg only one function amongst many contained by a 
> module - if that's the only code that requires maintenance/update.
> 
> Best not to create "technical debt" though!
> 
The main idea is to eventually catch some, otherwise "hidden", errors 
and produce better and cleaner code. Documentation is also a must.

Regards