eorroe / String.prototype.containsAll

Checks if all strings in passed array are included in string

String.prototype.containsAll proposal

Problem

Let's say I want to check whether a string contains a bunch of strings:

In ES5

var str = 'Hello this is a string';

// Using good old indexOf
str.indexOf('Hello') > -1 && str.indexOf('is'); // true

// Using ES6 (String.prototype.includes)
str.includes('Hello') && str.includes('is'); // true

So what happens if I want to do this with a bunch of strings it would be tedious and long, String.prototype.containsAll to the rescue:

Solution

var str = 'Hello this is a string';

str.containsAll(['Hello', 'is']); // true

//Let's add a string that it's not a part of str
str.containsAll(['Hello', 'is', 'notInString']) // false

So containsAll checks if all of the strings in the array are a part of the string that containsAll is being called on.

var str = 'Hello this is a string';

// Passing an array of strings where none are included in string that containsAll is called on
str.containsAll(['notInString']); // false

String.prototype.containsAll has a second parameter which is the index from where to check if any of the strings in the array are included:

var str = 'Hello this is a string';

// As before
str.containsAll(['Hello']); // true
// With Index
str.containsAll(['Hello'], 1); // false

// Multiple strings

// As before
str.containsAll(['Hello', 'is']); // true
// With Index
str.containsAll(['Hello', 'is'], 1); // false

Check out String.prototype.contains proposal

Here's the former discussion on ES-Discuss