slices

README

slices

Generic operations on slices: map, reduce, split, and group by.
Because writing for loops over and over is really boring.

Documentation

Overview

Package slices provides generic operations on slices, including map, reduce, split, and group by.

Index

• func GroupBy[K comparable, V any](src []V, keyFn func(V) K) map[K][]V
• func GroupByErr[K comparable, V any](src []V, keyFn func(V) (K, error)) (map[K][]V, error)
• func Map[A any, B any](src []A, mapper func(A) B) []B
• func MapErr[A any, B any](src []A, mapper func(A) (B, error)) ([]B, error)
• func Reduce[V any, A any](values []V, acc A, reducer func(acc A, val V) A) A
• func ReduceErr[V any, A any](values []V, acc A, reducer func(acc A, val V) (A, error)) (A, error)
• func Select[V any](src []V, selector func(V) bool) []V
• func SelectErr[V any](src []V, selector func(V) (bool, error)) ([]V, error)
• func Split[X any](src []X, partLen int) [][]X

Functions

func GroupBy

func GroupBy[K comparable, V any](src []V, keyFn func(V) K) map[K][]V

GroupBy indexes the given values by the result of the key function.

func GroupByErr

func GroupByErr[K comparable, V any](src []V, keyFn func(V) (K, error)) (map[K][]V, error)

GroupByErr allows the key function to fail and returns the failing error.

func Map

func Map[A any, B any](src []A, mapper func(A) B) []B

Map converts from one type to another using a mapper function.

func MapErr

func MapErr[A any, B any](src []A, mapper func(A) (B, error)) ([]B, error)

MapErr allows the mapper function to fail and returns the failing error.

func Reduce

func Reduce[V any, A any](values []V, acc A, reducer func(acc A, val V) A) A

Reduce a slice to a single value given an initial value and a reducer function.

func ReduceErr

func ReduceErr[V any, A any](values []V, acc A, reducer func(acc A, val V) (A, error)) (A, error)

ReduceErr allows the reducer function to fail and returns the failing error.

func Select

func Select[V any](src []V, selector func(V) bool) []V

Select returns a slice with values where the selector returned true.

func SelectErr

func SelectErr[V any](src []V, selector func(V) (bool, error)) ([]V, error)

SelectErr allows the selector to return an error which is then returned to the caller.

func Split

func Split[X any](src []X, partLen int) [][]X

Split given slice into equal sized parts. The last part may have an unequal length if the size of the source slice is not divisible by the required length without leaving a remainder.