Ubuntu 16 npm安装提示wanted: node >=6 current: node 4.2.6 npm 3.5.2

# 先在系统上安装好nodejs和npm
sudo apt-get install nodejs-legacy
sudo apt-get install npm

# 升级npm为最新版本
sudo npm install npm@latest -g

# 安装用于安装nodejs的模块n
sudo npm install -g n

# 通过n模块安装指定的nodejs（3选一）
sudo n latest
sudo n stable
sudo n lts

# 查看版本
sudo node -v

SyntaxError: Block-scoped declarations (let, const, function, class) not yet supported outside strict mode
    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 Function.Module.runMain (module.js:442:10)
    at startup (node.js:136

npm install -g n
sudo n stable
which n #查看n所安装路径
sudo ln -s n安装路径 /usr/local/bin/n # 软连接的bin下