There is still a lot of duplicated code --- the actual drawing of the rectangle --- around. If you need to copy and paste code, that is usually a sign of lacking abstractions. (Programmers call it a code smell.)
Functions are one way to express abstractions in Python. Let's take
turtle.reset() for example. It is actually an abstraction for a number of
steps, namely:
- Erase the drawing board
- Set the width and color back to default
- Move the turtle back to its initial position
A function can be defined with the def keyword in Python:
def line_without_moving():
turtle.forward(50)
turtle.backward(50)
You can access variables in functions as well:
size = 50
def line_without_moving():
turtle.forward(size)
turtle.backward(size)
Note
Python uses whitespace to identify blocks of code belonging together. While other languages use special characters (like curly brackets) in Python a block is introduced with a colon at the end of the line and commands within a deeper indentation level - usually 4 spaces. The block ends with the first line with a lesser indentation level.
Write a function that draws a square. Can you see how you could improve the tilted squares program with that and greatly relieve experimentation?
Write a function that draws a hexagon.
Now combine that function into a honeycomb.
def hexagon():
turtle.forward(100)
turtle.left(60)
turtle.forward(100)
turtle.left(60)
turtle.forward(100)
turtle.left(60)
turtle.forward(100)
turtle.left(60)
turtle.forward(100)
turtle.left(60)
turtle.forward(100)
turtle.left(60)
hexagon()
turtle.forward(100)
turtle.right(60)
hexagon()
turtle.forward(100)
turtle.right(60)
hexagon()
turtle.forward(100)
turtle.right(60)
hexagon()
turtle.forward(100)
turtle.right(60)
hexagon()
turtle.forward(100)
turtle.right(60)
hexagon()
turtle.forward(100)
turtle.right(60)