謝謝@ain和@JimB指引我朝着正確的方向前進。
基於在https://github.com/chzyer/readline/tree/master/example/readline-demo提供的示例中,我能夠實現期望的功能。
下面的代碼具有主命令newEntry
和newCategory
。如果用戶鍵入newEntry
並按下TAB,他可以從可用類別中進行選擇。 newCategory
命令允許添加一個新的自定義類別,該類別在下次執行newEntry
時立即可用。
package main
import (
"io"
"log"
"strconv"
"strings"
"github.com/chzyer/readline"
)
// completer defines which commands the user can use
var completer = readline.NewPrefixCompleter()
// categories holding the initial default categories. The user can add categories.
var categories = []string{"Category A", "Category B", "Category C"}
var l *readline.Instance
func main() {
// Initialize config
config := readline.Config{
Prompt: "\033[31m»\033[0m ",
HistoryFile: "/tmp/readline.tmp",
AutoComplete: completer,
InterruptPrompt: "^C",
EOFPrompt: "exit",
HistorySearchFold: true,
}
var err error
// Create instance
l, err = readline.NewEx(&config)
if err != nil {
panic(err)
}
defer l.Close()
// Initial initialization of the completer
updateCompleter(categories)
log.SetOutput(l.Stderr())
// This loop watches for user input and process it
for {
line, err := l.Readline()
if err == readline.ErrInterrupt {
if len(line) == 0 {
break
} else {
continue
}
} else if err == io.EOF {
break
}
line = strings.TrimSpace(line)
// Checking which command the user typed
switch {
// Add new category
case strings.HasPrefix(line, "newCategory"):
// Remove the "newCategory " prefix (including space)
if len(line) <= 12 {
log.Println("newCategory <NameOfCategory>")
break
}
// Append everything that comes behind the command as the name of the new category
categories = append(categories, line[12:])
// Update the completer to make the new category available in the cmd
updateCompleter(categories)
// Program is closed when user types "exit"
case line == "exit":
goto exit
// Log all commands we don't know
default:
log.Println("Unknown command:", strconv.Quote(line))
}
}
exit:
}
// updateCompleter is updates the completer allowing to add new command during runtime. The completer is recreated
// and the configuration of the instance update.
func updateCompleter(categories []string) {
var items []readline.PrefixCompleterInterface
for _, category := range categories {
items = append(items, readline.PcItem(category))
}
completer = readline.NewPrefixCompleter(
readline.PcItem("newEntry",
items...,
),
readline.PcItem("newCategory"),
)
l.Config.AutoComplete = completer
}
你是什麼意思 「(CLI)」 是什麼意思?也就是說,用戶將啓動你的程序,然後在「interacive shell」中工作,否則用戶將在系統shell中輸入完整的命令,並且你的程序執行它並退出? – ain
@ain好問題。我沒有想過這個。這與用例無關。因此:無論哪個更好實施。 – Chris
您指出的兩個示例非常不同,一個是readline實現,另一個使用bash的自動完成功能(使用不同的readline實現)。 – JimB