f

Documentation

Overview

Package f is a golang library implementing some basic algorithms.

The canonical import for this library is go.bug.st/f:

import "go.bug.st/f"

Index

• func Assert(condition bool, msg string, args ...any)
• func DiscardCh[T any](ch <-chan T)
• func Filter[T any](values []T, matcher Matcher[T]) []T
• func Map[T, U any](values []T, mapper Mapper[T, U]) []U
• func Must[T any](val T, err error) T
• func ParallelMap[T, U any](values []T, mapper Mapper[T, U], jobs ...int) []U
• func Ptr[T any](v T) *T
• func Reduce[T any](values []T, reducer Reducer[T], initialValue ...T) T
• func Uniq[T comparable](in []T) []T
• func UnwrapOrDefault[T any](ptr *T) T
• type Future
  • func (f *Future[T]) Await() T
  • func (f *Future[T]) Send(value T)
• type Mapper
• type Matcher
  • func Equals[T comparable](value T) Matcher[T]
  • func NotEquals[T comparable](value T) Matcher[T]
• type Reducer

Functions

func Assert

func Assert(condition bool, msg string, args ...any)

Assert panics if condition is false.

func DiscardCh

func DiscardCh[T any](ch <-chan T)

DiscardCh consumes all incoming messages from the given channel until it's closed.

func Filter

func Filter[T any](values []T, matcher Matcher[T]) []T

Filter takes a slice of type []T and a Matcher[T]. It returns a newly allocated slice containing only those elements of the input slice that satisfy the matcher.

func Map

func Map[T, U any](values []T, mapper Mapper[T, U]) []U

Map applies the Mapper function to each element of the slice and returns a new slice with the results in the same order.

func Must

func Must[T any](val T, err error) T

Must should be used to wrap a call to a function returning a value and an error. Must returns the value if the errors is nil, or panics otherwise.

func ParallelMap

func ParallelMap[T, U any](values []T, mapper Mapper[T, U], jobs ...int) []U

ParallelMap applies the Mapper function to each element of the slice and returns a new slice with the results in the same order. This is executed among multilple goroutines in parallel. If jobs is specified it will indicate the maximum number of goroutines to be spawned.

func Ptr

func Ptr[T any](v T) *T

Ptr returns a pointer to v.

func Reduce

func Reduce[T any](values []T, reducer Reducer[T], initialValue ...T) T

Reduce applies the Reducer function to all elements of the input values and returns the result.

func Uniq

func Uniq[T comparable](in []T) []T

Uniq return a copy of the input array with all duplicates removed

func UnwrapOrDefault

func UnwrapOrDefault[T any](ptr *T) T

UnwrapOrDefault returns the ptr value if it is not nil, otherwise returns the zero value.

Types

type Future

type Future[T any] struct {
	// contains filtered or unexported fields
}

Future is an object that holds a result value. The value may be read and written asynchronously.

func (*Future[T]) Await

func (f *Future[T]) Await() T

Await for a result from the Future, blocks until a result is available.

func (*Future[T]) Send

func (f *Future[T]) Send(value T)

Send a result in the Future. Threads waiting for result will be unlocked.

type Mapper

type Mapper[T, U any] func(T) U

Mapper is a function that converts a value of one type to another type.

type Matcher

type Matcher[T any] func(T) bool

Matcher is a function that tests if a given value matches a certain criteria.

func Equals

func Equals[T comparable](value T) Matcher[T]

Equals return a Matcher that matches the given value

func NotEquals

func NotEquals[T comparable](value T) Matcher[T]

NotEquals return a Matcher that does not match the given value

type Reducer

type Reducer[T any] func(T, T) T

Reducer is a function that combines two values of the same type and return the combined value.