purescript-heterogeneous-extrablatt 📰
Some additions of common use-cases when working with records and purescript-heterogeneous.
Usage guide
hsequenceRec
Recursively sequence a type constructor out of a record.
let
input :: SequenceInput
input =
{ a: Just 10
, b: "hello"
, c:
{ d: Just "world"
, e: true
, f: { g: Just true }
}
, h: 10
}
expected :: Maybe SequenceOutput
expected = Just
{ a: 10
, b: "hello"
, c:
{ d: "world"
, e: true
, f: { g: true }
}
, h: 10
}
(hsequenceRec input) `shouldEqual` expected
hmapRec
Recursively map a function over a record.
let
input :: MapInput
input =
{ a: 10
, b: "hello"
, c:
{ d: Just "world"
, e: 20
, f: { g: true, h: 30 }
}
, i: 40
}
f :: Int -> String
f i = show (i + 1)
expected :: MapOutput
expected =
{ a: "11"
, b: "hello"
, c:
{ d: Just "world"
, e: "21"
, f: { g: true, h: "31" }
}
, i: "41"
}
(hmapRec f input) `shouldEqual` expected
hmapKRec
Recursively map a natural transformation over a record.
let
input :: MapKInput
input =
{ a: Right 10
, b: "hello"
, c:
{ d: Left "world"
, e: 20
, f: { g: Right true, h: Left "broken" }
}
, i: Just 40
}
nt :: Either String ~> Maybe
nt = hush
expected :: MapKOutput
expected =
{ a: Just 10
, b: "hello"
, c:
{ d: Nothing
, e: 20
, f: { g: Just true, h: Nothing }
}
, i: Just 40
}
(hmapKRec nt input) `shouldEqual` expected
