package reason-standard

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Functions for manipulating trios of values

Functions for manipulating trios of values

type ('a, 'b, 'c) t = 'a * 'b * 'c

Create

val make : 'a -> 'b -> 'c -> 'a * 'b * 'c

Create a Tuple3.

Examples

Tuple3.create 3 "cat" false = (3, "cat", false)
List.map3 ~f:Tuple3.create [1;2;3] ['a'; 'b'; 'c'] [4.; 5.; 6.] =
  [(1, 'a', 4.), (2, 'b', 5.), (3, 'c', 6.)]
val ofArray : 'a array -> ('a * 'a * 'a) option

Create a tuple from the first two elements of an Array.

If the array is longer than two elements, the extra elements are ignored.

If the array is less than two elements, returns None

Examples

Tuple3.ofArray [|1; 2;3 |] = Some (1, 2, 3)
Tuple3.ofArray [|1; 2|] = None
Tuple3.ofArray [|4;5;6;7|] = Some (4, 5, 6)
val ofList : 'a list -> ('a * 'a * 'a) option

Create a tuple from the first two elements of a List.

If the list is longer than two elements, the extra elements are ignored.

If the list is less than two elements, returns None

Examples

Tuple3.ofList [1; 2; 3] = Some (1, 2, 3)
Tuple3.ofList [1; 2] = None
Tuple3.ofList [4; 5; 6; 7] = Some (4, 5, 6)

Basic operations

val first : ('a * 'b * 'c) -> 'a

Extract the first value from a tuple.

Examples

Tuple3.first (3, 4, 5) = 3
Tuple3.first ("john", "danger", "doe") = "john"
val second : ('a * 'b * 'c) -> 'b

Extract the second value from a tuple.

Examples

Tuple.second (3, 4, 5) = 4
Tuple.second ("john", "danger", "doe") = "danger"
val third : ('a * 'b * 'c) -> 'c

Extract the third value from a tuple.

Examples

Tuple.third (3, 4, 5) = 5
Tuple.third ("john", "danger", "doe") = "doe"
val initial : ('a * 'b * 'c) -> 'a * 'b

Extract the first and second values of a Tuple3 as a Tuple.

Examples

Tuple3.initial (3, "stressed", false) = (3, "stressed")
Tuple3.initial ("john", 16, true) = ("john", 16)
val tail : ('a * 'b * 'c) -> 'b * 'c

Extract the second and third values of a Tuple3 as a Tuple.

Examples

Tuple3.tail (3, "stressed", false) = ("stressed", false)
Tuple3.tail ("john", 16, true) = (16, true)

Modify

val rotateLeft : ('a * 'b * 'c) -> 'b * 'c * 'a

Move each value in the tuple one position to the left, moving the value in the first position into the last position.

Examples

Tuple.rotateLeft (3, 4, 5) = (4, 5, 3)
Tuple.rotateLeft ("was", "stressed", "then") = ("stressed", "then", "was")
val rotateRight : ('a * 'b * 'c) -> 'c * 'a * 'b

Move each value in the tuple one position to the right, moving the value in the last position into the first position.

Examples

Tuple.rotateRight (3, 4, 5) = (5, 3, 4)
Tuple.rotateRight ("was", "stressed", "then") = ("then", "was", "stressed")

Transform

val mapFirst : ('a * 'b * 'c) -> f:('a -> 'x) -> 'x * 'b * 'c

Transform the first value in a tuple.

Examples

Tuple3.mapFirst ~f:String.reverse ("stressed", 16, false) = ("desserts", 16, false)
Tuple3.mapFirst ~f:String.length ("stressed", 16, false) = (8, 16, false)
val mapSecond : ('a * 'b * 'c) -> f:('b -> 'y) -> 'a * 'y * 'c

Transform the second value in a tuple.

Examples

Tuple3.mapSecond ~f:Float.squareRoot ("stressed", 16., false) = ("stressed", 4., false)
Tuple3.mapSecond ~f:(~-) ("stressed", 16, false) = ("stressed", -16, false)
val mapThird : ('a * 'b * 'c) -> f:('c -> 'z) -> 'a * 'b * 'z

Transform the third value in a tuple.

Examples

Tuple3.mapThird ~f:not ("stressed", 16, false) ("stressed", 16, true)
val mapEach : ('a * 'b * 'c) -> f:('a -> 'x) -> g:('b -> 'y) -> h:('c -> 'z) -> 'x * 'y * 'z

Transform each value in a tuple by applying f to the first value, g to the second value and h to the third value.

Examples

Tuple3.mapEach
  ~f:String.reverse
  ~g:Float.squareRoot
  ~h:Bool.not
  ("stressed", 16., false) = ("desserts", 4., true)
val mapAll : ('a * 'a * 'a) -> f:('a -> 'b) -> 'b * 'b * 'b

Transform all the values of a tuple using the same function.

mapAll can only be used on tuples which have the same type for each value.

Examples

Tuple.mapAll ~f:Float.squareRoot (9., 16., 25.) = (3., 4., 5.)
Tuple.mapAll ~f:String.length ("was", "stressed", "then") = (3, 8, 4)

Convert

val toArray : ('a * 'a * 'a) -> 'a array

Turns a tuple into a List of length three.

This function can only be used on tuples which have the same type for each value.

Examples

Tuple3.toArray (3, 4, 5) = [3; 4; 5]
Tuple3.toArray ("was", "stressed", "then") = ["was"; "stressed"; "then"]
val toList : ('a * 'a * 'a) -> 'a list

Turns a tuple into a List of length three.

This function can only be used on tuples which have the same type for each value.

Examples

Tuple3.toList (3, 4, 5) = [3; 4; 5]
Tuple3.toList ("was", "stressed", "then") = ["was"; "stressed"; "then"]

Compare

val equal : ('a -> 'a -> bool) -> ('b -> 'b -> bool) -> ('c -> 'c -> bool) -> ('a, 'b, 'c) t -> ('a, 'b, 'c) t -> bool

Test two Tuple3s for equality, using the provided functions to test the first, second and third components.

Examples

Tuple.equal Int.equal String.equal Char.equal (1, "Fox", 'j') (1, "Fox", 'k') = true
Tuple.equal Int.equal String.equal Char.equal (1, "Fox", 'j') (2, "Hen", 'j') = false
val compare : ('a -> 'a -> int) -> ('b -> 'b -> int) -> ('c -> 'c -> int) -> ('a, 'b, 'c) t -> ('a, 'b, 'c) t -> int

Compare two Tuple3s, using the provided functions to compare the first components then, if the first components are equal, the second components, then the third components

Examples

Tuple.compare Int.compare String.compare Char.compare (1, "Fox", 'j') (1, "Fox", 'j') = 0
Tuple.compare Int.compare String.compare Char.compare (1, "Fox", 'j') (1, "Eel", 'j') = 1
Tuple.compare Int.compare String.compare Char.compare (1, "Fox", 'j') (2, "Fox", 'm') = -1