add split

split.ts

@@ -0,0 +1,31 @@
+import type { Equal, Expect } from '@type-challenges/utils'
+
+type cases = [
+  Expect<Equal<Split<'Hi! How are you?', 'z'>, ['Hi! How are you?']>>,
+  Expect<Equal<Split<'Hi! How are you?', ' '>, ['Hi!', 'How', 'are', 'you?']>>,
+  Expect<Equal<Split<'Hi! How are you?', ''>, ['H', 'i', '!', ' ', 'H', 'o', 'w', ' ', 'a', 'r', 'e', ' ', 'y', 'o', 'u', '?']>>,
+  Expect<Equal<Split<'', ''>, []>>,
+  Expect<Equal<Split<'', 'z'>, ['']>>,
+  Expect<Equal<Split<string, 'whatever'>, string[]>>,
+  Expect<Equal<Split<string, string>, string[]>>,
+  Expect<Equal<Split<'This is some real shit', string>, string[]>>,
+]
+
+type X = Split<'This is some real shit', string>;
+
+type Split<
+  S extends string,
+  Z extends string,
+> =
+S extends string
+  ? string extends S
+    ? string[]
+    : Z extends string
+      ? string extends Z
+        ? string[]
+        : S extends `${infer Head}${Z}${infer Tail}`
+          ? [Head, ...Split<Tail, Z>]
+          : Z extends '' ? [] : [S]
+      : never
+  : never
+;