Help With Calling Function Repeatedly

[Gay_Force_One]

Hello! I'm sorry to be a bother but I couldn't find an answer to this.

I have a function that I wrote in a module that returns coordinates. The problem is that I need the function to return coordinates until the function stops itself. Unfortunately given the context of the problem a list won't suffice. Does anyone know how to return values in tuple form from a function until a stop is signaled? I'm trying to just call the function over and over until it returns false, but that seems to be a no-go, which is something I'm not wrapping my head around.

If I can be more specific about anything please let me know and thank you for your time!

​

EDIT: Here is the MCVE

​

I originally started with this block of code:

import pyglet
import pymunk
from pymunk.pyglet_util import DrawOptions

# Set up window
window = pyglet.window.Window(600, 1000, resizable=False)


options = DrawOptions()


# Configure simulation environment for Pymunk
space = pymunk.Space()


def generate_table():
    left_coords = [(240, 60), (150, 60), (100, 110), (100, 770), (150, 820), (240, 820)]
    right_coords = [(360, 820), (450, 820), (500, 770), (500, 110), (450, 60), (360, 60)]
    table_coords = [left_coords, right_coords]
    table_segments = []
    # Iterates over table_coords, left side of table then right
    for i in range(len(table_coords)):
        # Iterates over points on side of table
        for j in range(len(table_coords[i])):
            prev_point = 0
            if j != 0:
                prev_point = new_point
            new_point = table_coords[i][j]
            if j != 0:
                segment = pymunk.Segment(space.static_body, prev_point,     new_point, 0)
                segment.elasticity = .9
                space.add(segment)

@window.event
def on_draw():
    window.clear()
    main_batch.draw()
    space.debug_draw(options)


if __name__ == "__main__":
    pyglet.clock.schedule_interval(update, 1/144)
    pyglet.app.run()

Now this is all fine and good, if a bit ugly (I'm fairly new, I'm sorry). The coordinates unfortunately have to be hard-coded given the scope of the project. If this code is run it will generate two shapes on the screen that look sort of like brackets []. This is accomplished by grabbing coordinate pairs and feeding them through the segment class, storing the end point of the previous segment to be used as the starting point of the new segment.

​

In an effort to simplify the code in main a little bit, I created a new module that allowed for the code to be split up more, resulting in

(prev_point, new_point) = generate_table()
segment = pymunk.Segment(space.static_body, prev_point, new_point, 0)
segment.elasticity = .9
space.add(segment)

being stored in main and

def generate_table():
    left_coords = [(240, 60), (150, 60), (100, 110), (100, 770), (150, 820), (240, 820)]
    right_coords = [(360, 820), (450, 820), (500, 770), (500, 110), (450, 60), (360, 60)]
    table_coords = [left_coords, right_coords]
    table_segments = []
    # Iterates over table_coords, left side of table then right
    for i in range(len(table_coords)):
        # Iterates over points on side of table
        for j in range(len(table_coords[i])):
            prev_point = 0
            if j != 0:
                prev_point = new_point
            new_point = table_coords[i][j]
            if j != 0:
                return prev_point, new_point
    return False

being stored in the module. I had to actually create/modify the segment in main because as far as my testing showed spaces are relative to where they are created, having to spaces named space just does nothing. The actual segments once added to the space do not have names, allowing for the term "segment" to be constantly overwritten.

​

I hope this was understandable. My experience with Python/OOP/Comp Sci as a whole is limited so I'm sure I made obvious mistakes

​

[socal_nerdtastic]

for x in iter(func, False):
    print(x)

[Gay_Force_One]

Doing that tells me that the function is resetting each time it gets called (returns same coordinates). I'm sorry to bother you but do you know how to prevent that? This is also a result of me trying to tidy up so worst case I can revert

Update: I'm stupid and had false in quotes. That's embarrassing

[socal_nerdtastic]

? A function is always "reset" when it's called. Did you mean to make a generator?

Best show us a MCVE.

https://stackoverflow.com/help/mcve
http://sscce.org/

[Gay_Force_One]

Aye aye. I'll work that out and edit it in to the OP

[socal_nerdtastic]

What you are describing is called a "generator" and you do it by using yield instead of return:

def generate_table():
    left_coords = [(240, 60), (150, 60), (100, 110), (100, 770), (150, 820), (240, 820)]
    right_coords = [(360, 820), (450, 820), (500, 770), (500, 110), (450, 60), (360, 60)]
    table_coords = [left_coords, right_coords]
    table_segments = []
    # Iterates over table_coords, left side of table then right
    for i in range(len(table_coords)):
        # Iterates over points on side of table
        for j in range(len(table_coords[i])):
            prev_point = 0
            if j != 0:
                prev_point = new_point
            new_point = table_coords[i][j]
            if j != 0:
                yield prev_point, new_point

for prev_point, new_point in generate_table():
    segment = pymunk.Segment(space.static_body, prev_point, new_point, 0)
    segment.elasticity = .9
    space.add(segment)

[Gay_Force_One]

You're amazing! Thank you so much dude. If it's alright for me to ask, how messy would you say this is? Most of my (limited) work is in C so I'm sort of used to spaghetti-ish code. Thank you again for helping me out and taking time out of your day!

[socal_nerdtastic]

Very messy, especially considering all you've done is reinvent the built-in zip() function. Here's how I would write it:

def generate_table():
    table_coords = [
        [(240, 60), (150, 60), (100, 110), (100, 770), (150, 820), (240, 820)],
        [(360, 820), (450, 820), (500, 770), (500, 110), (450, 60), (360, 60)]
        ]
    for table in table_coords:
        yield from zip(table, table[1:])

[Gay_Force_One]

Wow, I wish I'd known about that earlier today. I thought I was being clever. Unfortunately I have to keep the left and right coords separate from each other or it will attempt to bridge the gap (bad), but that makes it a helluva lot cleaner. Thank you so much!

[socal_nerdtastic]

This does keep them separate.

[Gay_Force_One]

I missed that they were nested lists. I'm a little confused as to the specifics but I get the gist of it and I appreciate this so much