柯里化（Currying）

安装loadsh

npm i --save lodash

  2. function curry(f) { // curry(f) 执行柯里化转换
  3.     return function(a) {
  4.       return function(b) {
  5.         return f(a, b);
  6.       };
  7.     };
  8.   }
  10.   // 用法
  11.   function sum(a, b) {
  12.     return a + b;
  13.   }
  15.   let curriedSum = curry(sum);
  17. //   console.log("🚀 ~ file: generator.js ~ line 15 ~ curriedSum", curriedSum(1));
  19. var _ = require('lodash');
  21. function log(date, importance, message) {
  22.     console.log(`[${date.getHours()}:${date.getMinutes()}] [${importance}] ${message}`);
  23.   }
  25.   log = _.curry(log);
  26. //   log(new Date(), "DEBUG", "some debug");
  27. //   log(new Date())("hello")("do something")
  28.   let logNow = log(new Date());
  30.   logNow("hello x2")("sss")

Blob

  1. <!DOCTYPE html>
  2. <html lang="en">
  4. <head>
  5.     <meta charset="UTF-8">
  6.     <meta http-equiv="X-UA-Compatible" content="IE=edge">
  7.     <meta name="viewport" content="width=device-width, initial-scale=1.0">
  8.     <title>Document</title>
  9. </head>
  11. <body>
  12.     <div>
  13.         <p>hello</p>
  14.     </div>
  15.     <input type="file" id="input">
  16.     <a id="btn">下载</a>
  17.     <div class="ims" id="imgs">
  19.     </div>
  20. </body>
  21. <script>
  22.     let str = `<div>
  23.         <p>hello</p>
  24.     </div>`
  25.     let myblod = new Blob([str], {
  26.         type: 'text/html'
  27.     })
  29.     myblod.text().then(res => console.log(res))
  30.     btn.onclick = function (e) {
  31.         this.setAttribute('download', 'test.html')
  32.         this.href = URL.createObjectURL(myblod)
  33.     }
  35.     input.onchange = function (e) {
  36.         console.log(e.target.files[0])
  37.         let file = e.target.files[0];
  38.         // let a = document.createElement('a')
  39.         // a.setAttribute('download', file.name);
  40.         // a.href = URL.createObjectURL(file)
  41.         // a.click()
  42.         let img = new Image();
  43.         let fileRead = new FileReader();
  44.         document.body.append(img)
  45.         fileRead.onload = function(e){
  46.             img.src = fileRead.result;
  47.         }
  48.         fileRead.readAsDataURL(file)
  49.         // img.src = URL.createObjectURL(file)
  50.         // imgs.append(img)
  51.     }
  52. </script>
  54. </html>