Add TypeScript declarations

index.js

@@ -1,3 +1,12 @@
+/**
+ * Calculates the edit distance using the Ukkonen algorithm.
+ *
+ * @param a - The first string.
+ * @param b - The second string.
+ * @param threshold (default Infinity) - The maximum edit distance to calculate.
+ * @returns The edit distance between string `a` and string `b`.
+ *          If the distance exceeds the threshold, returns the threshold.
+ */
 function ukkonen(a, b, threshold) {
   if (a === b) {
     return 0;

package.json

@@ -8,6 +8,7 @@
     "url": "https://github.com/sunesimonsen/ukkonen"
   },
   "main": "index.js",
+  "types": "./types/index.d.ts",
   "scripts": {
     "test": "mocha",
     "lint": "eslint . && prettier --check '**/*.{js,md,json}'",

types/index.d.ts

@@ -0,0 +1,11 @@
+/**
+ * Calculates the edit distance using the Ukkonen algorithm.
+ * @param a - The first string.
+ * @param b - The second string.
+ * @param threshold (default Infinity) - The maximum edit distance to calculate.
+ * @returns The edit distance between string `a` and string `b`.
+ *          If the distance exceeds the threshold, returns the threshold.
+ */
+declare function ukkonen(a: string, b: string, threshold?: number): number;
+
+export = ukkonen;