Referenced from lesson Method Chaining
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 |
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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 |
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t.filter(is-female) .build-column("kilos", kilograms) |
2 |
B |
Produces a table containing Maple, Nori and Toggle (in that order) |
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t.build-column("kilos", kilograms) .filter(is-heavy) |
3 |
C |
Produces a table containing only Fritz, with a single extra column called |
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t.filter(is-heavy) .build-column("kilos", kilograms) |
4 |
D |
Won’t run: will produce an error |
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t.build-column("kilos", kilograms) .filter(is-heavy) .order-by("sex", true) |
5 |
E |
Produces a table containing only Fritz, with two extra columns |
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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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