fn

README

fn

(yet another) functional primitives for Go -> Option with sql.Scanner / driver.Valuer functionality, JSON-serializable Result, composition, transactions primitive and moooore...

Install

go get github.com/pyrorhythm/fn

License

MIT

Documentation

Overview

Package fn provides functional programming primitives and different helpers

Index

• func Cast[T any](v any) T
• func Else[T any, M Container[T]](m M, fallback T) T
• func Fold[T, U any, M Container[T]](m M, onNil func() U, onVal func(T) U) U
• func If[T any](cond bool, then T, or T) T
• func Is[T any](v any) bool
• func Must[T any, M Container[T]](m M) T
• func Or[T any](p *T, v T) T
• func OrZero[T any](p *T) T
• func Valid[T comparable](v T) bool
• func ValidReflect[T any](v T) bool
• func Z[T any]() T
• type Container

Functions

func Cast

func Cast[T any](v any) T

func Else

func Else[T any, M Container[T]](m M, fallback T) T

Else returns the value if valid, otherwise returns fallback.

func Fold

func Fold[T, U any, M Container[T]](m M, onNil func() U, onVal func(T) U) U

Fold pattern matches over a container, calling onNil if invalid, onVal if valid.

func If

func If[T any](cond bool, then T, or T) T

If is a generic ternary operator.

func Is

func Is[T any](v any) bool

func Must

func Must[T any, M Container[T]](m M) T

Must returns the value if valid, otherwise panics.

func Or

func Or[T any](p *T, v T) T

Or returns first pointer as a value if pointer is not nil.

Else returns fallback T value, which was passed as a second argument.

func OrZero

func OrZero[T any](p *T) T

OrZero validates pointer and returns pointer as a value if pointer is not nil.

Else returns zero T value.

func Valid

func Valid[T comparable](v T) bool

Valid returns whether T is non-zero, where T implements [comparable]

func ValidReflect

func ValidReflect[T any](v T) bool

ValidReflect - valid through type-casting and [reflectValue]

NOT recommended if not implementing interfaces below, as reflection in Go may be from 25 to 50 times slower than stdlib.

If you really want to, you can check casted interfaces below, and implement one of them to avoid using reflection.

func Z

func Z[T any]() T

Z ...wait... OH! It's Zero Value!

Types

type Container

type Container[T any] interface {
	Val() T
	Valid() bool
}

Container provides value extraction from monadic types.