Filter unwanted attributes from an object

Keep ["nice", "good"]

-- { bad: 3, good: 1, nice: 500, evil: -3 }
-- => { good: 1, nice: 500 }

Grab value

Attr "foo"

-- { foo: 2 } => 2

Dig deeper

At "foo" $ Attr "bar"

-- { foo: { bar: 3 }} => 3

Map stuff

Map $ Attr "foo"

-- [{ foo:1, foo:2 }] => [1, 2]

Extract indices

Map $ Index 0

-- [[1,2], [3,4]] => [1, 3]

Create object

Obj $ fromList [
    ("first", Index 0)
  , ("second", Index 1)
  ]

-- ["hi", "bye"] => { first:"hi", second:"bye" }

Transform position

At "ranks" $ AtIndex 0 $ Attr "name"

-- {ranks: [ { name:"winner", score:12 }, { name:"Loser", score: 3 ]}
-- => "winner"

Combine objects

Merge (Attr "foo") (Attr "bar")

-- { foo: { a:1, b:2 }, bar: { b:3, c:4 } }
-- => { a:1, b:3, c:4 }