Type this line of code into the interactions area and hit "Enter":

(triangle 50 "solid" "red")

1

What is the name of this function?

2

What did the expression evaluate to?

3

How many arguments does triangle expect?

4

What data type does the triangle function produce?
(Numbers? Strings? Booleans?)

Catching Bugs

5 (triangle 20 "solid")

triangle: expects 3 arguments, but given 2: 20 solid at: line 1, column 0, in <interactions>

Can you spot the mistake?

6 (triangle "solid" "red" 20)

triangle: expects a non-negative number as 1st argument, but given: solid; other arguments were: red 20 at: line 1, column 0, in <interactions>

Can you spot the mistake?

7 (triangle 20 40 "solid" "red")

triangle: expects 3 arguments, but given 4: 20 40 solid red at: line 1, column 0, in <interactions>

Can you spot the mistake?

8 (triangle 20 solid "red")

solid: this variable is not defined at: line 1, column 0, in <interactions>

Can you spot the mistake?

9 (triangle 20 "striped" "red")

triangle: expects a style ("solid" / "outline") or an opacity value [0-255]) as 2nd argument, but given: "striped"; other arguments were: 20 "red" at: line 1, column 0, in <interactions>

Can you spot the mistake?

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