Function to avoid a global variable

[ast]

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)
...