Set
to emulate an abstract data structure called "set". A set is like an array, but it cannot contain duplicate values. The typical use for a set is to simply check for the presence of an item.
We can see how ES6 set object works in the example below-
```js
const set1 = new Set([1, 2, 3, 5, 5, 2, 0]);
console.log(set1);
// output: {1, 2, 3, 5, 0}
console.log(set1.has(1));
// output: true
console.log(set1.has(6));
// output: false
```
First, we will create an add method that adds a value to our set collection as long as the value does not already exist in the set.
Then we will create a remove method that removes a value from the set collection if it already exists.
And finally, we will create a size method that returns the number of elements inside the set collection.
add
method that adds a unique value to the set collection and returns true
if the value was successfully added and false
otherwise.
Create a remove
method that accepts a value and checks if it exists in the set. If it does, then this method should remove it from the set collection, and return true
. Otherwise, it should return false
.
Create a size
method that returns the size of the set collection.
Set
class should have an add
method.
testString: assert((function(){var test = new Set(); return (typeof test.add === 'function')}()), 'Your Set
class should have an add
method.');
- text: Your add
method should not add duplicate values.
testString: assert((function(){var test = new Set(); test.add('a'); test.add('b'); test.add('a'); var vals = test.values(); return (vals[0] === 'a' && vals[1] === 'b' && vals.length === 2)}()), 'Your add
method should not add duplicate values.');
- text: Your add
method should return true
when a value has been successfully added.
testString: assert((function(){var test = new Set(); var result = test.add('a'); return (result != undefined) && (result === true);}()), 'Your add
method should return true
when a value has been successfully added.');
- text: Your add
method should return false
when a duplicate value is added.
testString: assert((function(){var test = new Set(); test.add('a'); var result = test.add('a'); return (result != undefined) && (result === false);}()), 'Your add
method should return false
when a duplicate value is added.');
- text: Your Set
class should have a remove
method.
testString: assert((function(){var test = new Set(); return (typeof test.remove === 'function')}()), 'Your Set
class should have a remove
method.');
- text: Your remove
method should only remove items that are present in the set.
testString: assert.deepEqual((function(){var test = new Set(); test.add('a');test.add('b');test.remove('c'); return test.values(); })(), ['a', 'b'], 'Your remove
method should only remove items that are present in the set.');
- text: Your remove
method should remove the given item from the set.
testString: assert((function(){var test = new Set(); test.add('a');test.add('b');test.remove('a'); var vals = test.values(); return (vals[0] === 'b' && vals.length === 1)}()), 'Your remove
method should remove the given item from the set.');
- text: Your Set
class should have a size
method.
testString: assert((function(){var test = new Set(); return (typeof test.size === 'function')}()), 'Your Set
class should have a size
method.');
- text: The size
method should return the number of elements in the collection.
testString: assert((function(){var test = new Set(); test.add('a');test.add('b');test.remove('a');return (test.size() === 1)}()), 'The size
method should return the number of elements in the collection.');
```