learn

canvas/1.js

@@ -0,0 +1,5 @@
+class Regcode {
+  constructor() {
+
+  }
+}

curry.js

@@ -0,0 +1,23 @@
+function curry(fn, length) {
+  length = length || fn.length
+  return function(...args) {
+    if (args.length < length) {
+      return curry(sub_curry(fn, ...args),length - args.length)
+    } else {
+      return fn.call(this, ...args)
+    }
+  }
+}
+
+function sub_curry(fn, ...args) {
+  return function (...newArgs) {
+    return fn.apply(this, [...args, ...newArgs])
+  }
+}
+
+var fn = curry(function (a, b, c) {
+  return [a,b,c]
+})
+console.log(fn(1,2, 44))
+console.log(fn(1, 2)(44))
+console.log(fn(1)(2)(44))

专题系列/数组去重.js

@@ -64,4 +64,50 @@ function unique(array) {
 
 //es6最简单
 
-let unique = (a) => [...new Set(a)]
+// let unique = (a) => [...new Set(a)]
+var arr = [1, 1, '1', '1']
+
+function unique(arr) {
+  var res = []
+  for (var i = 0; i < arr.length; i++) {
+    // if (!(arr[i] in temp)) {
+    //   temp[arr[i]] = arr[i]
+    //   res[j++] = arr[i]
+    // }
+    // for (var j = 0; j < res.length; j++) {
+    //   if (arr[i] === res[j]) {
+    //     break
+    //   }
+    // }
+    // if (j === res.length) {
+    //   res.push(arr[i])
+    // }
+    if (res.indexOf(arr[i]) === -1) {
+      res.push(arr[i])
+    }
+  }
+  return res
+}
+
+function unique2(arr) {
+  var res = [], len = arr.length
+  var sortedArr = arr.concat().sort()
+  var seen
+  for (var i = 0; i < len; i++) {
+    if (!i || seen !== sortedArr[i]) {
+      res.push(sortedArr[i])
+    }
+    seen = sortedArr[i]
+  }
+  return res
+}
+
+function unique3(arr) {
+  var _set = {}, res = []
+  for (let i = 0; i < arr.length; i++) {
+    let key = typeof arr[i] + arr[i]
+    _set[key] || (_set[key] = true, res.push(arr[i]))
+  }
+  return res
+}
+console.log(unique3(arr))

专题系列/数组扁平化.html

@@ -11,13 +11,13 @@
 
     var arr = [1, [2, [3, 4]]];
 
-    function xx(arr) {
+    function flat(arr) {
       return arr.reduce((pre,next) => {
         return pre.concat(Array.isArray(next)? xx(next) : next)
       },[])
     }
 
-    console.log(xx(arr))
+    console.log(falt(arr))
   </script>
 </body>
 </html>

数组一些常用的方法实现.js

@@ -85,4 +85,5 @@ Array.prototype.find = function (cb, context) {
     let res = cb.call(context, arr[i], i, arr)
     if(res) return arr[i]
   }
-}
+}
+