Add TypeScript definition (#8)

index.d.ts

@@ -0,0 +1,16 @@
+export interface Options {
+	/**
+	 * Only match an exact string.
+	 *
+	 * @default false
+	 */
+	exact?: boolean
+}
+
+/**
+ * Returns a regex for matching email addresses.
+ *
+ * @param options - Configure the generated regular expression
+ * @returns Regex for matching email addresses.
+ */
+export default function emailRegex(options?: Options): RegExp;

index.test-d.ts

@@ -0,0 +1,8 @@
+import {expectType} from 'tsd-check';
+import emailRegex from '.';
+
+(async () => {
+	expectType<RegExp>(emailRegex());
+	expectType<RegExp>(emailRegex({}));
+	expectType<RegExp>(emailRegex({ exact: true }));
+})();

package.json

@@ -13,10 +13,11 @@
 		"node": ">=6"
 	},
 	"scripts": {
-		"test": "xo && ava"
+		"test": "xo && ava && tsd-check"
 	},
 	"files": [
-		"index.js"
+		"index.js",
+		"index.d.ts"
 	],
 	"keywords": [
 		"text",
@@ -34,6 +35,12 @@
 	],
 	"devDependencies": {
 		"ava": "*",
+		"tsd-check": "^0.3.0",
 		"xo": "*"
+	},
+	"xo": {
+		"ignores": [
+			"*.ts"
+		]
 	}
 }