Completed ES6 ✨

Author: suhailroushan13

Advanced-JavaScript/14. ES6/10.js

@@ -82,3 +82,76 @@ Unlike Maps, WeakMaps are not iterabl
 */
 
 
+
+/*
+JavaScript WeakMap
+The WeakMap is similar to a Map. However, WeakMap can only contain objects as keys. For example,
+
+const weakMap = new WeakMap();
+console.log(weakMap); // WeakMap {} 
+
+let obj = {};
+
+// adding object (element) to WeakMap
+weakMap.set(obj, 'hello');
+
+console.log(weakMap); // WeakMap {{} => "hello"}
+Run Code
+When you try to add other data types besides objects, WeakMap throws an error. For example,
+
+const weakMap = new WeakMap();
+
+// adding string as a key to WeakMap
+weakMap.set('obj', 'hello');
+Run Code
+// throws error
+// TypeError: Attempted to set a non-object key in a WeakMap
+WeakMap Methods
+WeakMaps have methods get(), set(), delete(), and has(). For example,
+
+const weakMap = new WeakMap();
+console.log(weakMap); // WeakMap {} 
+
+let obj = {};
+
+// adding object (element) to WeakMap
+weakMap.set(obj, 'hello');
+
+console.log(weakMap); // WeakMap {{} => "hello"}
+
+// get the element of a WeakMap
+console.log(weakMap.get(obj)); // hello
+
+// check if an element is present in WeakMap
+console.log(weakMap.has(obj)); // true
+
+// delete the element of WeakMap
+console.log(weakMap.delete(obj)); // true
+
+console.log(weakMap); // WeakMap {} 
+Run Code
+WeakMaps Are Not iterable
+Unlike Maps, WeakMaps are not iterable. For example,
+
+const weakMap = new WeakMap();
+console.log(weakMap); // WeakMap {} 
+
+let obj = {};
+
+// adding object (element) to WeakMap
+weakMap.set(obj, 'hello');
+
+
+// looping through WeakMap
+for (let i of weakMap) {
+
+    console.log(i);  // TypeError
+}
+
+ 
+ 
+ 
+ 
+ 
+ 
+*/

Advanced-JavaScript/14. ES6/11.js

@@ -0,0 +1,254 @@
+/*
+avaScript Set and WeakSet
+In this tutorial, you will learn about JavaScript Sets and WeakSets with the help of examples.
+
+The JavaScript ES6 has introduced two new data structures, i.e Set and WeakSet.
+
+Set is similar to an array that allows us to store multiple items like numbers, strings, objects, etc. However, unlike an array, a set cannot contain duplicate values.
+
+Create JavaScript Set
+To create a Set, you need to use the new Set() constructor. For example,
+
+// create Set
+const set1 = new Set(); // an empty set
+console.log(set1); // Set {}
+
+// Set with multiple types of value
+const set2 = new Set([1, 'hello', {count : true}]);
+console.log(set2); // Set {1, "hello", {count: true}}
+Run Code
+When duplicate values are passed to a Set object, the duplicate values are excluded.
+
+// Set with duplicate values
+const set3 = new Set([1, 1, 2, 2]);
+console.log(set3); // Set {1, 2}
+Run Code
+Access Set Elements
+You can access Set elements using the values() method and check if there is an element inside Set using has() method. For example,
+
+const set1 = new Set([1, 2, 3]);
+
+// access the elements of a Set
+console.log(set1.values()); // Set Iterator [1, 2, 3]
+Run Code
+You can use the has() method to check if the element is in a Set. For example,
+
+const set1 = new Set([1, 2, 3]);
+
+// check if an element is in Set
+console.log(set1.has(1));
+Run Code
+Adding New Elements
+You can add elements to a Set using the add() method. For example,
+
+const set = new Set([1, 2]);
+console.log(set.values());
+
+// adding new elements
+set.add(3);
+console.log(set.values());
+
+// adding duplicate elements
+// does not add to Set
+set.add(1);
+console.log(set.values());
+Run Code
+Output
+
+Set Iterator [1, 2]
+Set Iterator [1, 2, 3]
+Set Iterator [1, 2, 3]
+Removing Elements
+You can use the clear() and the delete() method to remove elements from a Set.
+
+The delete() method removes a specific element from a Set. For example,
+
+const set = new Set([1, 2, 3]);
+console.log(set.values()); // Set Iterator [1, 2, 3]
+
+// removing a particular element
+set.delete(2);
+console.log(set.values()); // Set Iterator [1, 3]
+Run Code
+The clear() method removes all elements from a Set. For example,
+
+const set = new Set([1, 2, 3]);
+console.log(set.values()); // Set Iterator [1, 2, 3]
+
+// remove all elements of Set
+set.clear();
+console.log(set.values()); // Set Iterator []
+Run Code
+Iterate Sets
+You can iterate through the Set elements using the for...of loop or forEach() method. The elements are accessed in the insertion order. For example,
+
+const set = new Set([1, 2, 3]);
+
+// looping through Set
+for (let i of set) {
+    console.log(i);
+}
+Run Code
+Output
+
+1
+2
+3
+JavaScript WeakSet
+The WeakSet is similar to a Set. However, WeakSet can only contain objects whereas a Set can contain any data types such as strings, numbers, objects, etc. For example,
+
+const weakSet = new WeakSet();
+console.log(weakSet); // WeakSet {}
+
+let obj = {
+    message: 'Hi',
+    sendMessage: true
+}
+
+// adding object (element) to WeakSet
+weakSet.add(obj);
+
+console.log(weakSet); // WeakSet {{message: "Hi", sendMessage: true}}
+Run Code
+When you try to add other data types besides objects, WeakSet throws an error. For example,
+
+// trying to add string to WeakSet
+weakSet.add('hello');
+
+// throws error
+// TypeError: Attempted to add a non-object key to a WeakSet
+console.log(weakSet);
+Run Code
+WeakSet Methods
+WeakSets have methods add(), delete(), and has(). For example,
+
+const weakSet = new WeakSet();
+console.log(weakSet); // WeakSet {}
+
+const obj = {a:1};
+
+// add to a weakSet
+weakSet.add(obj);
+console.log(weakSet); // WeakSet {{a: 1}}
+
+// check if an element is in Set
+console.log(weakSet.has(obj)); // true
+
+// delete elements
+weakSet.delete(obj);
+console.log(weakSet); // WeakSet {}
+Run Code
+WeakSets Are Not iterable
+Unlike Sets, WeakSets are not iterable. For example,
+
+const weakSet = new WeakSet({a:1});
+
+// looping through WeakSet
+for (let i of weakSet) {
+
+    // TypeError
+    console.log(i);
+}
+Run Code
+Mathematical Set Operations
+In JavaScript, Set does not provide built-in methods for performing mathematical operations such as union, intersection, difference, etc. However, we can create programs to perform those operations.
+
+Example: Set Union Operation
+// perform union operation
+// contain elements of both sets
+function union(a, b) {
+    let unionSet = new Set(a);
+    for (let i of b) {
+        unionSet.add(i);
+    }
+    return unionSet
+}
+
+// two sets of fruits
+let setA = new Set(['apple', 'mango', 'orange']);
+let setB = new Set(['grapes', 'apple', 'banana']);
+
+let result = union(setA, setB);
+
+console.log(result);
+Run Code
+Output
+
+Set {"apple", "mango", "orange", "grapes", "banana"}
+Example: Set Intersection Operation
+// perform intersection operation
+// elements of set a that are also in set b
+function intersection(setA, setB) {
+    let intersectionSet = new Set();
+
+    for (let i of setB) {
+        if (setA.has(i)) {
+            intersectionSet.add(i);
+        }
+    }
+    return intersectionSet;
+}
+
+// two sets of fruits
+let setA = new Set(['apple', 'mango', 'orange']);
+let setB = new Set(['grapes', 'apple', 'banana']);
+
+let result = intersection(setA, setB);
+
+console.log(result);
+Run Code
+Output
+
+Set {"apple"}
+Example: Set Difference Operation
+// perform difference operation
+// elements of set a that are not in set b
+function difference(setA, setB) {
+    let differenceSet = new Set(setA)
+    for (let i of setB) {
+        differenceSet.delete(i)
+    }
+    return differenceSet
+}
+
+// two sets of fruits
+let setA = new Set(['apple', 'mango', 'orange']);
+let setB = new Set(['grapes', 'apple', 'banana']);
+
+let result = difference(setA, setB);
+
+console.log(result);
+Run Code
+Output
+
+Set {"mango", "orange"}
+Example: Set Subset Operation
+// perform subset operation
+// true if all elements of set b is in set a
+function subset(setA, setB) {
+    for (let i of setB) {
+        if (!setA.has(i)) {
+            return false
+        }
+    }
+    return true
+}
+
+// two sets of fruits
+let setA = new Set(['apple', 'mango', 'orange']);
+let setB = new Set(['apple', 'orange']);
+
+let result = subset(setA, setB);
+
+console.log(result);
+Run Code
+Output
+
+true
+ 
+ 
+ 
+ 
+ 
+ 
+*/