go-readline-ny is a one-line input library for CUI applications written in Go. It is designed to be extensible to meet diverse needs and has been used in the command-line shell NYAGOS for a long time.
- Emacs-like key-bindings
- Input history
- Word completion (file names, command names, or any names in given array)
- Syntax highlighting
- Supported platforms: Windows and Linux
- Full Unicode (UTF8) support, including:
- Surrogate-pair
- Emojis (via clipboard)
- Zero-width joiner (via clipboard)
- Variation selectors (via clipboard pasted with Ctrl-Y)
- Add-Ons:
- SKK (Japanese input method editor)
- Multi-lines Editing
package main
import (
"context"
"fmt"
"github.com/nyaosorg/go-readline-ny"
)
func main() {
var editor readline.Editor
text, err := editor.ReadLine(context.Background())
if err != nil {
fmt.Printf("ERR=%s\n", err.Error())
} else {
fmt.Printf("TEXT=%s\n", text)
}
}If the target platform includes Windows, you have to import and use go-colorable like example2.go .
This is a sample demonstrating prompt change, syntax highlighting, filename completion, history browsing, and access to the operating system clipboard.
package main
import (
"context"
"fmt"
"io"
"os"
"os/exec"
"regexp"
"strings"
"github.com/atotto/clipboard"
"github.com/mattn/go-colorable"
"github.com/nyaosorg/go-readline-ny"
"github.com/nyaosorg/go-readline-ny/completion"
"github.com/nyaosorg/go-readline-ny/keys"
"github.com/nyaosorg/go-readline-ny/simplehistory"
)
type OSClipboard struct{}
func (OSClipboard) Read() (string, error) {
return clipboard.ReadAll()
}
func (OSClipboard) Write(s string) error {
return clipboard.WriteAll(s)
}
func main() {
history := simplehistory.New()
editor := &readline.Editor{
PromptWriter: func(w io.Writer) (int, error) {
return io.WriteString(w, "\x1B[36;22m$ ") // print `$ ` with cyan
},
Writer: colorable.NewColorableStdout(),
History: history,
Highlight: []readline.Highlight{
{Pattern: regexp.MustCompile("&"), Sequence: "\x1B[33;49;22m"},
{Pattern: regexp.MustCompile(`"[^"]*"`), Sequence: "\x1B[35;49;22m"},
{Pattern: regexp.MustCompile(`%[^%]*%`), Sequence: "\x1B[36;49;1m"},
{Pattern: regexp.MustCompile("\u3000"), Sequence: "\x1B[37;41;22m"},
},
HistoryCycling: true,
PredictColor: [...]string{"\x1B[3;22;34m", "\x1B[23;39m"},
ResetColor: "\x1B[0m",
DefaultColor: "\x1B[33;49;1m",
Clipboard: OSClipboard{},
}
editor.BindKey(keys.CtrlI, &completion.CmdCompletionOrList2{
// Characters listed here are excluded from completion.
Delimiter: "&|><;",
// Enclose candidates with these characters when they contain spaces
Enclosure: `"'`,
// String to append when only one candidate remains
Postfix: " ",
// Function for listing candidates
Candidates: completion.PathComplete,
})
// If you do not want to list files with double-tab-key,
// use `CmdCompletion2` instead of `CmdCompletionOrList2`
fmt.Println("Tiny Shell. Type Ctrl-D to quit.")
for {
text, err := editor.ReadLine(context.Background())
if err != nil {
fmt.Printf("ERR=%s\n", err.Error())
return
}
fields := strings.Fields(text)
if len(fields) <= 0 {
continue
}
cmd := exec.Command(fields[0], fields[1:]...)
cmd.Stdout = os.Stdout
cmd.Stderr = os.Stderr
cmd.Stdin = os.Stdin
cmd.Run()
history.Add(text)
}
}package main
import (
"context"
"fmt"
"io"
"os"
"github.com/nyaosorg/go-readline-ny"
"github.com/nyaosorg/go-readline-ny/completion"
"github.com/nyaosorg/go-readline-ny/keys"
)
func mains() error {
var editor readline.Editor
editor.PromptWriter = func(w io.Writer) (int, error) {
return io.WriteString(w, "menu> ")
}
candidates := []string{"list", "say", "pewpew", "help", "exit", "Space Command"}
// If you do not want to list files with double-tab-key,
// use `CmdCompletion2` instead of `CmdCompletionOrList2`
editor.BindKey(keys.CtrlI, &completion.CmdCompletionOrList2{
// Characters listed here are excluded from completion.
Delimiter: "&|><;",
// Enclose candidates with these characters when they contain spaces
Enclosure: `"'`,
// String to append when only one candidate remains
Postfix: " ",
// Function for listing candidates
Candidates: func(field []string) (forComp []string, forList []string) {
if len(field) <= 1 {
return candidates, candidates
}
return nil, nil
},
})
ctx := context.Background()
for {
line, err := editor.ReadLine(ctx)
if err != nil {
return err
}
fmt.Printf("TEXT=%#v\n", line)
}
return nil
}
func main() {
if err := mains(); err != nil {
fmt.Fprintln(os.Stderr, err)
os.Exit(1)
}
}MIT License
