Referenced from lesson Table Methods

You have the following functions defined below (read them carefully!):

fun lookup-fixed(animal): animal["fixed"]              	  end
fun is-dog(animal):    	animal["species"] == "dog"        end
fun is-old(animal):    	animal["age"] > 10                end
fun label(animal):     	text(animal["name"], 20, "red")   end

The table t below represents four animals from the shelter:

name sex age fixed species pounds

"Toggle"

"female"

12

true

"dog"

48

"Fritz"

"male"

4

false

"dog"

92

"Nori"

"female"

6

true

"dog"

35.3

"Sunflower"

"female"

2

false

cat

51.6

Below are a list of expressions that use table methods. What table do we get, after evaluating each one? Match each expression (left) to the table we get (right).

t.order-by("age", true)

1

A

Produces a table with Toggle, Fritz, and Nori - but not Sunflower.

t.order-by("pounds", false)

2

B

Produces a table of all four animals, sorted youngest-to-oldest

t.build-column("sticker", label)

3

C

Produces a table, with only Toggle.

t.filter(is-old)

4

D

Produces an identical table with an extra column called "dog", whose values are true, true, true, false

t.filter(lookup-fixed)

5

E

Produces a table containing only Nori and Toggle.

t.filter(is-dog)

6

F

Produces a table with all four animals, sorted from heaviest to lightest.

t.build-column("dog", is-dog)

7

G

Won’t run: will produce an error

t.filter(label)

8

H

Produces an identical table with an extra column called "sticker", whose values are images

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