Getting started set example is confusing

[tim-styra]

Change to a list of words instead of numbers.

[tsandall]

In the example, we generate a set of numbers from array indices. This always confuses new users because they expect the set to contain the contents of the array.

> p[x] { a = [1,2,3,4]; a[x] }
> p[x] > 1
+---+
| x |
+---+
| 2 |
| 3 |
+---+

Change this to something like...

> items = ["pizza", "apples", "bread", "coffee"]
> users = {"bob": {"likes": [0, 2]}, "alice": {"likes": [1, 2, 3]}}
> likes[[name, item]] { index = users[name].likes[_]; item = items[index] }

And then show examples...

> likes[["alice", item]] # what does alice like?
+----------+
|   item   |
+----------+
| "apples" |
| "bread"  |
| "coffee" |
+----------+
> likes[[name, "bread"]] # who likes bread?
+---------+
|  name   |
+---------+
| "alice" |
| "bob"   |
+---------+