singleflight

This repo is a hard fork of golang.org/x/sync/singleflight that adds generics to the Group type so that there is no need for type assertion when using the library.

Install

go get marwan.io/singleflight@latest

Usage

Instead of writing

var g Group
v, _, _ := g.Do("key", func() (interface{}, error) {
    return "bar", nil
})
useString(v.(string))

you can now just write

var g Group[string]
v, _, _ := g.Do("key", func() (string, error) {
    return "bar", nil
})
useString(v)

Diff:

- var g Group
+ var g Group[string]
- v, _, _ := g.Do("key", func() (interface{}, error) {
+ v, _, _ := g.Do("key", func() (string, error) {
    return "bar", nil
})
- useString(v.(string))
+ useString(v)