Can I iterate over turtles / classes?

Question

I have four turtles I want to be all at the same y pos and pass in an x pos to have them in a line along the bottom of the screen.

I was wondering if this is possible with a for loop?

code:

from turtle import *

canvas = Screen()
bg_img = "assets\\board.gif"

canvas.setup(1.0, 1.0, None, None)
canvas.bgpic(bg_img)
canvas.bgcolor("#222")
canvas.title("Boardgame")

start_ypos = -250
starta = (-20, start_ypos)

a = Turtle()
b = Turtle()
c = Turtle()
d = Turtle()

a.shape("square")
a.speed(0)
a.penup()
a.setpos(starta)

`for t in [a, b, c, d]: t.setpos(...)`? Note that wildcard imports (`from foo import *`) are generally discouraged, as it makes it difficult to see where the names you're using have come from. — jonrsharpe, Feb 03 '15 at 14:48
As for the from turtle import * this is a file with just turtle in, it was more for convenience. — Thomas Carroll, Feb 03 '15 at 14:55
@jonrsharpe's answer is right, don't know if he wants to post it as an answer. Had no idea about using an index as a class thingy. — Thomas Carroll, Feb 03 '15 at 15:01

score 2 · Accepted Answer · answered Feb 03 '15 at 15:03

2

Yes, you can iterate over your Turtle instances, for example by putting them into a list and looping over it:

for turtle_instance in [a, b, c, d]:
    turtle_instance.setpos(...)

In fact, it is probably easier to start with them in a list:

turtles = [Turtle() for _ in range(4)]  # see "list comprehension" if unfamiliar

and then access turtles[0] rather than a.

answered Feb 03 '15 at 15:03

jonrsharpe

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Quick question regarding `_` in list comprehension; does it do anything special or could I put something like `i` there and get the same result? – Thomas Carroll Feb 03 '15 at 15:06
2

@ThomasCarroll it's just the convention for *"I'm not actually going to use this value"*, see e.g. http://stackoverflow.com/q/5893163/3001761 – jonrsharpe Feb 03 '15 at 15:07

Can I iterate over turtles / classes?

1 Answers1