Package opt implements an optional-type, for the Go programming language.
In other programming languages, an optional-type might be know as: a option-type, or a maybe-type.
Online documentation, which includes examples, can be found at: http://godoc.org/github.com/reiver/go-opt
Here is an example optional-type that can hold a string:
import "github.com/reiver/go-opt"
//
var op opt.Optional[string] // the default value is nothing.
// ...
if opt.Nothing[string]() == op {
fmt.Println("nothing")
}
// ...
op = opt.Something("Hello world! 👾")
// ...
switch op {
case op.Nothing[string]():
//@TODO
case op.Something("apple"):
//@TODO
case op.Something("banana"):
//@TODO
case op.Something("cherry"):
//@TODO
default:
//@TODO
}
// ...
value, found := op.Get()
if found {
fmt.Println("VALUE:", value)
} else {
fmt.Println("nothing")
}
To import package opt use import
code like the follownig:
import "github.com/reiver/go-opt"
To install package opt do the following:
GOPROXY=direct go get https://github.com/reiver/go-opt
Package opt was written by Charles Iliya Krempeaux