Skip to content

Instantly share code, notes, and snippets.

@kylelemons
Created September 8, 2011 18:49
Show Gist options
  • Save kylelemons/1204276 to your computer and use it in GitHub Desktop.
Save kylelemons/1204276 to your computer and use it in GitHub Desktop.
Enum types (bitshifted too)
package main
import (
"fmt"
"strings"
)
type foo int
const (
One foo = iota
Two
Three
Four
)
var fooNames = [...]string{
One: "One",
Two: "Two",
Three: "Three",
Four: "Four",
}
func (f foo) String() string {
return fooNames[f]
}
type mask int
const (
Read mask = 1 << iota
Write
Async
)
var maskNames = [...]string{
Read: "Read",
Write: "Write",
Async: "Async",
}
func (m mask) String() string {
var masks []string
for i := Read; i <= Async; i <<= 1 {
if m & i != 0 {
masks = append(masks, maskNames[i])
}
}
return strings.Join(masks, " | ")
}
func main() {
for _, val := range []foo{One,Two,Three,Four} {
fmt.Printf("(%T) %v %v\n", val, int(val), val)
}
for _, val := range []mask{
Read,
Write,
Async,
Read | Async,
Write | Async,
Read | Write,
Read | Write | Async,
} {
fmt.Printf("(%T) %v %v\n", val, int(val), val)
}
}
(main.foo) 0 One
(main.foo) 1 Two
(main.foo) 2 Three
(main.foo) 3 Four
(main.mask) 1 Read
(main.mask) 2 Write
(main.mask) 4 Async
(main.mask) 5 Read | Async
(main.mask) 6 Write | Async
(main.mask) 3 Read | Write
(main.mask) 7 Read | Write | Async
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment