Sorry for having conflated the core of the matter with all
the Borg shenanigans, that's where I found the problem in my
real code, so there :-)
Consider this:
#----------------------------------------------------
class Surprise:
def __init__(self, with_type_annotation=False):
if with_type_annotation:
try:
self.does_not_exist:bool
print('does_not_exist does exist')
except AttributeError:
print('does_not_exist does not exist')
return
try:
self.does_not_exist
print('does_not_exist does exist')
except AttributeError:
print('does_not_exist does not exist')
Surprise(with_type_annotation = False)
Surprise(with_type_annotation = True)
#----------------------------------------------------
Is this how it is supposed to be ?
> ...and so we're addressing the important question: the try-test is for
> existence, cf for
> some value.
>
> This can also be achieved by using the attribute in a legal expression, eg:
...
> Might this remove the confusion (ref: @Mats):
>
> self.already_initialized:bool == True
Not for me as that would _create_ already_initialized on the
instance. It would not allow me to test for it.
> >Which seems akin constructs for generating compatibility
> >between versions.
>
> versions of ?
Of the language. Sometimes one tests for existence of a given
class in a module and defines said class oneself if it does
not exist. But that's leading astray.
> What is the intent: a class where each instance is aware of every other
> instance - yet
> the word "Singleton" implies there's only one (cf a dict full of ...)?
The latter.
Regards,
Karsten
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