Referenced from lesson Method Chaining (Spring, 2021)

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

fun is-female(r): r["sex"] == "female"  end
fun kilograms(r): r["pounds"] / 2.2     end
fun is-heavy(r):  r["kilos"] > 25       end

The table t below represents four animals from the shelter:

name sex age fixed pounds

"Toggle"

"female"

3

true

48

"Fritz"

"male"

4

true

92

"Nori"

"female"

6

true

35.3

"Maple"

"female"

3

true

51.6

Match each Pyret expression (left) to the description of what it does (right). Note: one description might match multiple expressions!

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

1

A

Produces a table containing Toggle, Nori and Maple, with an extra column showing their weight in kilograms

 
t.filter(is-female)
  .build-column("kilos", kilograms)

2

B

Produces a table containing Maple, Nori and Toggle (in that order)

 
t.build-column("kilos", kilograms)
  .filter(is-heavy)

3

C

Produces a table containing only Fritz.

 
t.filter(is-heavy)
  .build-column("kilos", kilograms)

4

D

Won’t run: will produce an error

 
t.build-column("kilos", kilograms)
  .filter(is-heavy)
  .order-by("sex", true)

5

E

Produces a table containing only Fritz, with two extra columns.

 
t.build-column("female", is-female)
  .build-column("kilos", kilograms)
  .filter(is-heavy)

6

F

Produces a table containing Maple and Fritz

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