Also escape -

This enables you to escape a string that is inserted into a regex, for example, into a character class.

Fixes #9

index.d.ts

@@ -1,16 +1,18 @@
 /**
 Escape RegExp special characters.
 
+You can also use this to escape a string that is inserted into the middle of a regex, for example, into a character class.
+
 @example
 ```
 import escapeStringRegexp = require('escape-string-regexp');
 
-const escapedString = escapeStringRegexp('how much $ for a 🦄?');
-//=> 'how much \\$ for a 🦄\\?'
+const escapedString = escapeStringRegexp('How much $ for a 🦄?');
+//=> 'How much \\$ for a 🦄\\?'
 
 new RegExp(escapedString);
 ```
 */
-declare const escapeStringRegexp: (str: string) => string;
+declare const escapeStringRegexp: (string: string) => string;
 
 export = escapeStringRegexp;

index.js

@@ -1,6 +1,6 @@
 'use strict';
 
-const matchOperatorsRegex = /[|\\{}()[\]^$+*?.]/g;
+const matchOperatorsRegex = /[|\\{}()[\]^$+*?.-]/g;
 
 module.exports = string => {
 	if (typeof string !== 'string') {

readme.md

@@ -15,12 +15,14 @@ $ npm install escape-string-regexp
 ```js
 const escapeStringRegexp = require('escape-string-regexp');
 
-const escapedString = escapeStringRegexp('how much $ for a 🦄?');
-//=> 'how much \\$ for a 🦄\\?'
+const escapedString = escapeStringRegexp('How much $ for a 🦄?');
+//=> 'How much \\$ for a 🦄\\?'
 
 new RegExp(escapedString);
 ```
 
+You can also use this to escape a string that is inserted into the middle of a regex, for example, into a character class.
+
 
 ## License
 

test.js

@@ -7,3 +7,10 @@ test('main', t => {
 		'\\\\ \\^ \\$ \\* \\+ \\? \\. \\( \\) \\| \\{ \\} \\[ \\]'
 	);
 });
+
+test('escapes `-`', t => {
+	t.is(
+		escapeStringRegexp('foo - bar'),
+		'foo \\- bar'
+	);
+});