Naming things

Page 6

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If you want the turtle to draw a square you say:

You can't just say SQUARE. The turtle doesn't know what a square is. But you can teach him! First click the "Edall" button. A box pops up. That box is called the editor. Write TO SQUARE in the box. Then write the Logo code that makes a square. Then write END. Like this:

(You don't have to put spaces in front of the lines within the name. But it's easier to read that way.)

Then select "File" and "Save and Exit". That's it. Now you have taught the turtle what SQUARE means. Now you can just write SQUARE and the turtle will draw a square.

Try:

You can CS and draw more squares. The turtle remembers.

Can you teach the turtle what TRIANGLE means? Try.

You can use names that you have taught the turtle inside other names. Maybe you have taught him WINDOW and DOOR. Then you can use those words when you teach him HOUSE.

Now you can teach the turtle what anything means. You can teach him what a house is. Or what a boat is. Or something else. You can also combine new words and REPEAT. Maybe like this:

How did I draw that? First I changed the color to 3. Then I wrote this:

See? Teaching the turtle new words makes everything easier!

These are the words we know so far. TO is new:

Logo word	What it means
FD 100	Walk forward 100 steps
BK 100	Walk backward 100 steps
LT 90	Turn left (good for drawing squares)
RT 90	Turn right (good for drawing squares)
LT 120	Turn left (good for drawing triangles)
RT 120	Turn right (good for drawing triangles)
CS	Remove everything you have drawn
HOME	Move back to the starting point (and draw a line)
PU	Lift the pen so you won't draw when you walk
PD	Put the pen towards the screen again
REPEAT 10 [       ]	Repeat what's in the box 10 times
SETPC 4	Change the pen to pen number 4
TO ... END	Remember the word after TO in the future

We also taught him a new word: SQUARE.

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