Define overloads

Author: EzioMercer

src/lib/es5.d.ts

@@ -4577,3 +4577,23 @@ interface Date {
      */
     toLocaleTimeString(locales?: string | string[], options?: Intl.DateTimeFormatOptions): string;
 }
+
+type Split<Source extends string, Separator extends string> = Source extends `${infer Left}${Separator}${infer Right}`
+    ? [...(string extends Left ? string[] : [`${Left}`]), ...Split<Right, Separator>]
+    : Source extends ""
+        ? Separator extends ""
+            ? []
+            : [""]
+        : string extends Source
+            ? string[]
+            : [Source];
+
+interface String {
+    split<Source extends string, Separator extends string>(
+        this: Source,
+        separator: Separator,
+        limit?: undefined,
+    ): Split<Source, Separator>;
+
+    split(separator: string | RegExp, limit: 0): [];
+}