Function evalSpecialCommand

kernel.go:726–770

execute special command. line must start with '%'

(ir *interp.Interp, outerr OutErr, line string)

// execute special command. line must start with '%'
func evalSpecialCommand(ir *interp.Interp, outerr OutErr, line string) {
	const help string = `
available special commands (%):
%cd [path]
%go111module {on|off}
%help

execute shell commands ($): $command [args...]
example:
$ls -l
`

	args := strings.SplitN(line, " ", 2)
	cmd := args[0]
	arg := ""
	if len(args) > 1 {
		arg = args[1]
	}
	switch cmd {
	case "%cd":
		if arg == "" {
			home, err := os.UserHomeDir()
			if err != nil {
				panic(fmt.Errorf("error getting user home directory: %v", err))
			}
			arg = home
		}
		err := os.Chdir(arg)
		if err != nil {
			panic(fmt.Errorf("error setting current directory to %q: %v", arg, err))
		}
	case "%go111module":
		if arg == "on" {
			ir.Comp.CompGlobals.Options |= base.OptModuleImport
		} else if arg == "off" {
			ir.Comp.CompGlobals.Options &^= base.OptModuleImport
		} else {
			panic(fmt.Errorf("special command %s: expecting a single argument 'on' or 'off', found: %q", cmd, arg))
		}
	case "%help":
		outerr.out.Write([]byte(help))
	default:
		panic(fmt.Errorf("unknown special command: %q\n%s", line, help))
	}
}

// execute shell command. line must start with '$'
func evalShellCommand(ir *interp.Interp, outerr OutErr, line string) {