在修改了~/.bashrc 中的变量刷新系统环境后出现了这个问题：

$ ls

Command 'ls' is available in '/bin/ls'

The command could not be located because '/bin' is not included in the PATH environment variable.

ls: command not found

料想肯定是环境变量配置有问题。

于是：

$ vim ~/.bashrc

Command 'vim' is available in '/usr/bin/vim'

The command could not be located because '/usr/bin' is not included in the PATH environment variable.

vim: command not found

意思是在本地环境变量中找不到这个指令了。

尝试直接访问vim在本地中的指令存放地址使用：

$ /usr/bin/vim ~/.bashrc

访问成功。

发现最后添加的export之后的 $PATH 缺了$。补全，wq保存后，重新刷新环境变量：

$ source ~/.bashrc

问题即解决。