I found what I think is peculiar behaviour by python 3.4. I made these small files to illustrate the problem I am facing.
To focus on the problem, I now have a python program(module), peculiar.py, containing a class, and some functions. One of the functions are instantiating points from the class Point. When I left click the pygame window, a point is instantiated from the class Point, by this function, add_point. In the command window the instances created this way is listed. Everything is ok with this. As we can see the points crated are added to the points_list and listed in the command window.
Right clicking the window makes the very same function (add_point) called by a function in another module (pec_controls.py). A point is then instantiated, but it seems to be added to a new or different points_list, adding only points instantiated by right clicking the window. If we toggle between right and left clicking the window, the class toggles between two different versions of the points_list.
I could understand this behavior if the class was called directly from pec_controls.py, i.e. the point was instantiated in pec_control.py, but not as now, when it is the very same function in peculiar.py that calls the class in all instances. I am kind of "passing the scope" to pec_control module when I right click, but I think one should expect the scope to be returned, when that module then calls add_point, back in peculiar.py. It is very unexpected to put it mildly that where you call a function from is significant to it's, and or, a class's behavior.
Could someone explain the rationale behind this behavior by python? Is there something I forgot, to make all the instances appear in the same list?
Here is pec_controls.py:
import peculiar, sys, pygame
def clicked_right():
peculiar.add_point()
and here is peculiar.py:
# peculiar.py
# Sample to show peculiar behaviour by python 3.4, or python in general?
# Left clicking window instantiates point by this module alone(see command window).
# Right clicking window instantiates point from pec_controls.py module.
# Right clicking, instead of calling add_point function directly, as left clicking does, calls function in pec_controls.py, which then calls the add_point function in this module.
# What is peculiar is that this is resulting in Class Point seeming to make a new list of the global list points_list,
# only containing the items instantiated from pec_controls module(i.e. by right clicking window) ref. command window .
# Left clicking again, makes the Class go back to the original list, adding "leftclicked" point instances as usual.
# Apparently there is now two different lists? Is this a bug or intended?
import pygame, sys, pec_controls
from pygame.locals import *
FPS = 10
points_list = []
class Point():
def __init__(self):
points_list.append(self)
self.position = (10 * len(points_list), 10 * len(points_list))
print("Class says: ",len(points_list), "points")
def update(self):
self.rect.x = self.position[0]
self.rect.y = self.position[1]
pass
def add_point( x = None, y = None):
display_frame()
point = Point()
for i in points_list: # The points created by calling the class from controls.py via btn_add_point_clicked_left.
print ("add_point says", i, i.position) # ref: Display frame which prints out the points made by calling the class from main
print ("add_point", points_list) # This writes out points in points_list !!!!!!!!
def process_events():
for event in pygame.event.get():
if event.type == pygame.QUIT:
return True
if event.type == pygame.MOUSEBUTTONUP :
if event.button == 1:
add_point() # Instantiates a point via btn_add_point_clicked. (Ok/Normal)
print("Left Click")
elif event.button == 3:
pec_controls.clicked_right() # Instantiates a point via pec_controls module via add_point. (Peculiar result !!!!)
print("Right Click")
pass
return False
def display_frame():
for i in points_list: # Writes out the points in the global list points_list
print ("display says", i, i.position) #
print("display", points_list) #
def main(): # Main function
pygame.init()
main.screen = pygame.display.set_mode((200,200),0,32)
main.clock = pygame.time.Clock()
point = Point() # Instantiates a point from main of this module
point.position =(100,200)
add_point() # Instatiates a point from main via the function add_point
main.done = False
while not main.done:
main.done = process_events()
main.clock.tick(FPS)
#display_frame()
pygame.quit()
if __name__ == "__main__":
main()
