fun

Documentation

Overview

Package fun provides reusable general-purpose functions (Const, Swap, Curry) and data structures (Unit, Pair, Either).

Index

• Variables
• func Cast[A any](i Any) (a A, err error)
• func Compose[A any, B any, C any](f func(A) B, g func(B) C) func(A) C
• func Const[A any, B any](b B) func(A) B
• func ConstUnit[B any](b B) func(Unit) B
• func Curry[A any, B any, C any](f func(a A, b B) C) func(a A) func(b B) C
• func Identity[A any](a A) A
• func Max[T constraints.Ordered](x, y T) T
• func Min[T constraints.Ordered](x, y T) T
• func Nothing[A any]() A
• func PairBoth[A any, B any](p Pair[A, B]) (A, B)
• func PairV1[A any, B any](p Pair[A, B]) A
• func PairV2[A any, B any](p Pair[A, B]) B
• func RecoverToErrorVar(name string, err *error)
• func RecoverToLog(name string)
• func Swap[A any, B any, C any](f func(a A) func(b B) C) func(b B) func(a A) C
• func ToString[A any](a A) string
• func UnsafeCast[A any](i Any) A
• type Any
  • func CastAsInterface[A any](a A) Any
• type Number
• type Pair
  • func NewPair[A any, B any](a A, b B) Pair[A, B]
  • func PairSwap[A any, B any](p Pair[A, B]) Pair[B, A]
• type Predicate
  • func IsEqualTo[A comparable](a A) Predicate[A]
  • func Not[A any](p Predicate[A]) Predicate[A]
• type Unit

Variables

var Unit1 = Unit{}

Unit1 is the value of type Unit.

Functions

func Cast

func Cast[A any](i Any) (a A, err error)

Cast converts interface {} to ordinary type A. It'a simple operation i.(A) represented as a function. In case the conversion is not possible, returns an error.

func Compose

func Compose[A any, B any, C any](f func(A) B, g func(B) C) func(A) C

Compose executes the given functions in sequence.

func Const

func Const[A any, B any](b B) func(A) B

Const creates a function that will ignore it's input and return the specified value.

func ConstUnit

func ConstUnit[B any](b B) func(Unit) B

ConstUnit creates a function that will ignore it's Unit input and return the specified value.

func Curry

func Curry[A any, B any, C any](f func(a A, b B) C) func(a A) func(b B) C

Curry takes a function that has two arguments and returns a function with two argument lists.

func Identity

func Identity[A any](a A) A

Identity function returns the given value unchanged.

func Max

func Max[T constraints.Ordered](x, y T) T

Max - returns the maximum value. See https://go.dev/blog/intro-generics

func Min

func Min[T constraints.Ordered](x, y T) T

Min - returns the minimum value. See https://go.dev/blog/intro-generics

func Nothing

func Nothing[A any]() A

Nothing panics. However, can be used anywhere where type A is needed.

func PairBoth

func PairBoth[A any, B any](p Pair[A, B]) (A, B)

PairBoth returns both parts of the pair.

func PairV1

func PairV1[A any, B any](p Pair[A, B]) A

PairV1 returns the first element of the pair.

func PairV2

func PairV2[A any, B any](p Pair[A, B]) B

PairV2 returns the second element of the pair.

func RecoverToErrorVar

func RecoverToErrorVar(name string, err *error)

RecoverToErrorVar recovers and places the recovered error into the given variable

func RecoverToLog

func RecoverToLog(name string)

RecoverToLog in case of error just logs it.

func Swap

func Swap[A any, B any, C any](f func(a A) func(b B) C) func(b B) func(a A) C

Swap returns a curried function with swapped order of arguments.

func ToString

func ToString[A any](a A) string

ToString converts the value to string using `Sprintf` `%v`.

func UnsafeCast

func UnsafeCast[A any](i Any) A

UnsafeCast converts interface {} to ordinary type A. It'a simple operation i.(A) represented as a function. In case the conversion is not possible throws a panic.

Types

type Any

type Any interface{}

func CastAsInterface

func CastAsInterface[A any](a A) Any

CastAsInterface casts a value of an arbitrary type as interface {}.

type Number

type Number interface {
	constraints.Integer |
		constraints.Float |
		constraints.Complex
}

Number is a generic number interface that covers all Go number types.

type Pair

type Pair[A any, B any] struct {
	V1 A
	V2 B
}

Pair is a data structure that has two values.

func NewPair

func NewPair[A any, B any](a A, b B) Pair[A, B]

NewPair constructs the pair.

func PairSwap

func PairSwap[A any, B any](p Pair[A, B]) Pair[B, A]

PairSwap returns a pair with swapped parts.

type Predicate

type Predicate[A any] func(A) bool

Predicate is a function with a boolean result type.

func IsEqualTo

func IsEqualTo[A comparable](a A) Predicate[A]

IsEqualTo compares two arguments for equality.

func Not

func Not[A any](p Predicate[A]) Predicate[A]

Not negates the given predicate.

type Unit

type Unit struct{}

Unit is a type that has only a single value.