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Python

Posted by nathaniel marquez
nathaniel marquez
222 Points

Learning the inner workings of a Python Function.

Hello ALL.

I am currently learning Python Functions, reading Tracebacks and using the debugger in VSCode.

Here is some code I put together but I get an recursion depth error. 

def preloader_goal(g):
    goal_met = preloader_goal
    print(goal_met(f"Thats great you got all {preloader_goal} of your boxes loaded."))
preloader_goal(20)

The error I get is: [Previous line repeated 995 more time] RecursionError: maximum recursion depth exceeded while getting the str of an object.

I was trying to get a custom output of goal_met when preloader_goal was called. What am I not seeing?

nathaniel marquez
nathaniel marquez
222 Points

Here is the newest variation of what was wanting to do it works, but i am not sure why its working.

goal = 20

def preloader_goal(goal)
    if goal == 20:
        return("You have reached the go goal of 20.")
    else:
        return("You have not reached the goal of 20.")

print(preloader_goal(goal))

So I guess what I am asking now is ... is this current variation an actual version of the previous code sample or is it just a whole other way of writing the code?

1 Answer

Steven Parker
Steven Parker
230,274 Points
Steven Parker
Steven Parker
230,274 Points

The first example is infinitely recursive, as the function calls itself unconditionally (after giving itself a new name of "goal_met"). Recursive functions must always have a test for an exit condition to avoid exceeding system limits.

The second example just performs a simple test and returns one of two options. It doesn't call any other functions (including itself, so no recursion).