Singleton in go

Question

How does one implement the Singleton design pattern in the go programming language?

Answer 1

You should be aware that Once.Do is serious about executing the code only once. That means, the code is always executed only once, even though it might have panicked:

from https://golang.org/pkg/sync/#Once.Do

If f (note: the once logic) panics, Do considers it to have returned; future calls of Do return without calling f.

I used mutexes instead to ensure unique initialisation of a global configuration variable to overcome this restriction:

• https://golang.org/pkg/sync/#Mutex
• https://gobyexample.com/mutexes