随着 Mac 下终端的使用日益增多，系统默认的 bash 已经满足不了需求了，于是有了更为强劲的 fish 和 zsh，以及它们各自的强心剂 Oh-My-Fish 和 Oh-My-Zsh. 我的选择是 Fish 和 Oh-My-Fish。

到目前为止，最新的 fish 2.2.0 于 2015 年 7 月 12 日发布，Release notes 如下 http://fishshell.com/release_notes.html，其中显著改变有：

• Abbreviations: the new `abbr` command allows for interactively-expanded abbreviations, allowing quick access to frequently-used commands (#731).
• Vi mode: run `fish_vi_mode` to switch fish into the key bindings and prompt familiar to users of the Vi editor (#65).
• New inline and interactive pager, which will be familiar to users of zsh (#291).
• Underlying architectural changes: the `fishd` universal variable server has been removed as it was a source of many bugs and security problems. Notably, old fish sessions will not be able to communicate universal variable changes with new fish sessions. For best results, restart all running instances of `fish`.
• The web-based configuration tool has been redesigned, featuring a prompt theme chooser and other improvements.
• New German, Brazilian Portuguese, and Chinese translations.

我对第二点比较感兴趣，即增加了 vi 模式，在 fish 下运行 fish_vi_mode 命令， 或者在 ~/.config/fish/config.fish 中加上 fish_vi_mode 便自动进入 vi 模式。 Read More

枚举的声明很简单, 像 enum Gender { Male, Female }, 其余事情就是 Java 编译器帮我们干的了，所以 enum 也就是一块语法糖。有了枚举确实是很方便，避免了传统常量的无范围性。那么编译器到底在后面做了什么呢？以及理解了这个之后我们可以怎么去使用 Java 的枚举, 下面就从这个例子说起：

public enum Gender {
    Male,
    Female
}

把上面的编译成 Gender.class, 然后用  javap -c Gender 反编译出来就是 Read More

1var net = require('net');
2net.createServer(function (socket) {
3  socket.on('data', function (data) {
4    socket.write('received: ' + data);
5  });
6}).listen('/tmp/node_tcp.sock');

✗ telnet /tmp/node_tcp.sock
Trying /tmp/node_tcp.sock...
Connected to (null).
Escape character is '^]'.
Hello World!
received: Hello World!