Add class and function implementation for 1st example

tshemsedinov · tshemsedinov · commit 51cff0f36f9f · 2018-11-04T23:18:11.000+02:00
diff --git a/JavaScript/2-class.js b/JavaScript/2-class.js
@@ -0,0 +1,46 @@
+'use strict';
+
+class TimeoutCollection {
+  constructor(timeout) {
+    this.timeout = timeout;
+    this.collection = new Map();
+    this.timers = new Map();
+  }
+
+  set(key, value) {
+    const timer = this.timers.get(key);
+    if (timer) clearTimeout(timer);
+    const timeout = setTimeout(() => {
+      this.delete(key);
+    }, this.timeout);
+    this.collection.set(key, value);
+    this.timers.set(key, timeout);
+  }
+
+  get(key) {
+    return this.collection.get(key);
+  }
+
+  delete(key) {
+    const timer = this.timers.get(key);
+    if (timer) {
+      clearTimeout(timer);
+      this.collection.delete(key);
+      this.timers.delete(key);
+    }
+  }
+
+  toArray() {
+    return [...this.collection.entries()];
+  }
+}
+
+// Usage
+
+const hash = new TimeoutCollection(1000);
+hash.set('uno', 1);
+setTimeout(() => {
+  hash.set('due', 2);
+  hash.set('tre', 3);
+  console.dir({ array: hash.toArray() });
+}, 1500);
diff --git a/JavaScript/3-function.js b/JavaScript/3-function.js
@@ -0,0 +1,42 @@
+'use strict';
+
+const timeoutCollection = timeout => {
+  const collection = new Map();
+  const timers = new Map();
+  const facade = {};
+
+  facade.set = (key, value) => {
+    const prevTimer = timers.get(key);
+    if (prevTimer) clearTimeout(prevTimer);
+    const timer = setTimeout(() => {
+      collection.delete(key);
+    }, timeout);
+    collection.set(key, value);
+    timers.set(key, timer);
+  };
+
+  facade.get = key => collection.get(key);
+
+  facade.delete = key => {
+    const timer = timers.get(key);
+    if (timer) {
+      clearTimeout(timer);
+      collection.delete(key);
+      timers.delete(key);
+    }
+  };
+
+  facade.toArray = () => [...collection.entries()];
+
+  return facade;
+};
+
+// Usage
+
+const hash = timeoutCollection(1000);
+hash.set('uno', 1);
+setTimeout(() => {
+  hash.set('due', 2);
+  hash.set('tre', 3);
+  console.dir({ array: hash.toArray() });
+}, 1500);
