Awesome Code Snippet

收藏一些比较惊艳的代码片段

JavaScript

模板字符串替换

/**
 * format string
 * @example
 * "Hello {fn}. My full name is {my}.".templ({fn:"Alan", ln:"Wei", my:function(){return this.fn + " " + this.ln;}}); 
 * "Hello Alan. My full name is Alan Wei."
 * 
 * */
String.prototype.templ = function (json) {
    var args = arguments;
    var paras = Array.prototype.splice.call(args, 1, args.length - 1);

    var fnReg = /\{\{([\w\s\+\.\(\)'\-";]+)\}\}/g;
    var fnText = this.replace(fnReg, function (g0, g1) {
        var innerFunction = new Function(g1);
        return innerFunction.apply(json, paras);
    });

    var placeHoldReg = /\{(\w+|\d*|_*)\}/g;
    return fnText.replace(placeHoldReg, function (g0, g1) {
        var value = json[g1];
        return typeof (value) === "function" ? value.apply(json, paras) : value;
    });
};

迭代指定目录和文件

const path = require("path");
const fs = require("fs");

/**
 * 迭代目录
 * @param {string} root 根目录 
 * @returns {ArrayLike<{path: string, relative: string, state: fs.Stats}>}
 */
function* ioRecursive(root) {
  yield* (function* foreach(dir) {
    for (let item of fs.readdirSync(dir, { encoding: "utf-8" })) {
      const fullPath = path.join(dir, item);
      const state = fs.statSync(fullPath);

      yield {
        path: fullPath,
        relative: path.relative(root, fullPath),
        state: state
      };

      if (state.isDirectory()) {
        yield* foreach(fullPath);
      }
    }
  })(root);
}