must

Generic error handling with panic, recover, and defer. Requires Go 1.18 or later.

Usage:

// main.go
package main

import (
	"fmt"
	"os"

	"github.com/mcesar/must"
)

func main() {
	fmt.Println(f())
}

func f() (err error) {
	defer must.Handle(&err)
	f := must.Do(os.Open("file"))
	defer f.Close()
	// ...
	return nil
}

To run:

$ go run main.go

Benchmarks:

$ go test -bench=.
goos: darwin
goarch: arm64
pkg: github.com/mcesar/must
BenchmarkMustErrorHandlingWithoutDelay-8       	 9594230	       114.1 ns/op
BenchmarkRegularErrorHandlingWithoutDelay-8    	73931268	        15.71 ns/op
BenchmarkMustErrorHandlingWith10msDelay-8      	     100	  11777532 ns/op
BenchmarkRegularErrorHandlingWith10msDelay-8   	     100	  11590843 ns/op

Documentation

func Do

func Do[A any](a A, err error) A

Do returns a or panics if err != nil

func Do0

func Do0(err error)

Do panics if err != nil

func Do2

func Do2[A, B any](a A, b B, err error)

Do2 returns a and b or panics if err != nil

func Handle

func Handle(err *error)

Handle sets err to recovered value if it is an error

func Handlef

func Handlef(err *error, str string)

Handlef sets err to recovered value if it is an error, wrapped according to the formatting string specified