angular cli ng命令给出“意外令牌=”

npm公司 使用此命令行:

npm install -g @angular/cli

安装成功,但当我尝试使用 commande然后我出现了这个错误:

root@errabi-Lenovo-G560:/home/errabi/Desktop# ng help
/usr/local/lib/node_modules/@angular/cli/models/config/config.js:17
    constructor(_configPath, schema, configJson, fallbacks = []) {
                                                           ^

SyntaxError: Unexpected token =
    at exports.runInThisContext (vm.js:53:16)
    at Module._compile (module.js:374:25)
    at Object.Module._extensions..js (module.js:417:10)
    at Module.load (module.js:344:32)
    at Function.Module._load (module.js:301:12)
    at Module.require (module.js:354:17)
    at require (internal/module.js:12:17)
    at Object.<anonymous> (/usr/local/lib/node_modules/@angular/cli/models/config.js:3:18)
    at Module._compile (module.js:410:26)
    at Object.Module._extensions..js (module.js:417:10)

对这个问题有什么想法吗提前谢谢