Bitmasker 
Bitmasker is a tool used to automate the creation of helper methods when dealing with bitmask-type constant flags. Given the name of an unsigned integer type T that has constants defined, bitmasker will create a new self-contained Go source file implementing the BitMask and fmt.Stringer interfaces.
Getting Started
To get up and running, follow the normal go install procedure:
go install github.com/go-curses/bitmasker
Example Usage
Bitmasker is intended to be used with go:generate but can operated standalone as well. For example:
Given this snippet:
package mental
//go:generate bitmasker -type=State
type State uint
const (
Unconscious State = 0
Conscious State = (1 << iota)
Meditative
Distracted
Entertained = Distracted
)
Standalone usage:
bitmasker -type=State
Using go-generate
go generate
In both cases a new file named "state_bitmask.go" will be created with the following contents:
// Code generated by "bitmasker -type=State"; DO NOT EDIT.
package mental
import "strconv"
func (i State) Has(m State) bool {
return i&m != 0
}
func (i State) Set(m State) State {
return i | m
}
func (i State) Clear(m State) State {
return i &^ m
}
func (i State) Toggle(m State) State {
return i ^ m
}
const (
_State_name_0 = "Unconscious"
_State_name_1 = "Conscious"
_State_name_2 = "Meditative"
_State_name_3 = "Distracted"
)
func (i State) String() string {
switch {
case i == 0:
return _State_name_0
case i == 2:
return _State_name_1
case i == 4:
return _State_name_2
case i == 8:
return _State_name_3
default:
return "State(" + strconv.FormatInt(int64(i), 10) + ")"
}
}
Running the tests
Unit tests are provided and can be invoked using the normal Go pattern:
go test
Authors
License
This project is licensed under the LGPL (specifically v3) - see the LICENSE.md file for details.
Acknowledgments
- Thanks to Golang.org for the stringer program that bitmasker sources are derived from.
