// RunWithPromptAndPrelude runs a REPL with the given prompt and prelude.
func RunWithPromptAndPrelude(l *loop.Loop, prompt, prelude string) error {
if prompt == "" {
prompt = ">"
}
prompt = strings.Trim(prompt, " ")
prompt += " "
rl, err := readline.New(prompt)
if err != nil {
return err
}
l.VM().Set("console", map[string]interface{}{
"log": func(c otto.FunctionCall) otto.Value {
s := make([]string, len(c.ArgumentList))
for i := 0; i < len(c.ArgumentList); i++ {
s[i] = c.Argument(i).String()
}
rl.Stdout().Write([]byte(strings.Join(s, " ") + "\n"))
rl.Refresh()
return otto.UndefinedValue()
},
"warn": func(c otto.FunctionCall) otto.Value {
s := make([]string, len(c.ArgumentList))
for i := 0; i < len(c.ArgumentList); i++ {
s[i] = c.Argument(i).String()
}
rl.Stderr().Write([]byte(strings.Join(s, " ") + "\n"))
rl.Refresh()
return otto.UndefinedValue()
},
})
if prelude != "" {
if _, err := io.Copy(rl.Stderr(), strings.NewReader(prelude+"\n")); err != nil {
return err
}
rl.Refresh()
}
var d []string
for {
ll, err := rl.Readline()
if err != nil {
if err == readline.ErrInterrupt {
if d != nil {
d = nil
rl.SetPrompt(prompt)
rl.Refresh()
continue
}
break
}
return err
}
if len(d) == 0 && ll == "" {
continue
}
d = append(d, ll)
s := strings.Join(d, "\n")
if _, err := parser.ParseFile(nil, "repl", s, 0); err != nil {
rl.SetPrompt(strings.Repeat(" ", len(prompt)))
} else {
rl.SetPrompt(prompt)
d = nil
t := looptask.NewEvalTask(s)
// don't report errors to the loop - this lets us handle them and
// resume normal operation
t.SoftError = true
l.Add(t)
l.Ready(t)
v, err := <-t.Value, <-t.Error
if err != nil {
if oerr, ok := err.(*otto.Error); ok {
io.Copy(rl.Stdout(), strings.NewReader(oerr.String()))
} else {
io.Copy(rl.Stdout(), strings.NewReader(err.Error()))
}
} else {
f, err := format(v, 80, 2, 5)
if err != nil {
panic(err)
}
rl.Stdout().Write([]byte(f + "\n"))
}
}
rl.Refresh()
}
return rl.Close()
}
