安装OCaml先去下载一个opam二进制版本，比如opam1.2.2x86\_64Linux下载opam(https://www.oschina.net/action/GoToLink?urlhttps%3A%2F%2Fgithub.com%2Focaml%2Fopam%2Freleases)重命名为opam，放到/usr