Function to avoid a global variable

[ast]

Le 28/04/2020 à 08:51, ast a écrit :
> Le 27/04/2020 à 04:46, Bob van der Poel a écrit :
>> Does this make as much sense as anything else? I need to track calls to a
>> function to make sure it doesn't get called to too great a depth. I had a
>> global which I inc/dec and then check in the function. Works fine, but 
>> I do
>> need to keep a global around just for this.
>>
>> So ... instead I wrote a short function:
>>
>>   def parseStack(inc, depth=[0]):
>>       if depth[0] > 50:
>>           ... report error and die nicely
>>      depth[0] += inc
>>
>> This gets rid of the global, and it moves my error check out of the main
>> code as well. But, I never feel all that great about using a list in the
>> function call for static storage.
>>
> 
> 
> Using a callable object is the best way to define a function
> with a memory
> 
> class ParseStack:
>      def __init__(self):
>          self.depth=0
>      def __call__(self, inc, reset=True):
>          if reset:
>              self.depth = 0
>          if self.depth > 50:
>              ... report error
>          self.depth += 1
>          ... do your stuff
> 
> parse_stack = ParseStack()
> 
> and use "function" parse_stack
> 
> parse_stack(43)
> ...


def __call__(self, inc, reset=False):