diff --git a/typescript/core/decorator/decorator.ts b/typescript/core/decorator/decorator.ts
index 63437a9f1e..d7e7e664f5 100644
--- a/typescript/core/decorator/decorator.ts
+++ b/typescript/core/decorator/decorator.ts
@@ -59,3 +59,28 @@ export class Model<U extends {types?: {[key: string]: unknown} | {}, context?: R
 
     computed: {[key: string]: () => unknown} | {};
 }
+
+/* 分享一段很好看的代码
+// union to intersection of functions
+type UnionToIoF<U> =
+    (U extends any ? (k: (x: U) => void) => void : never) extends
+    ((k: infer I) => void) ? I : never
+
+// return last element from Union
+type UnionPop<U> = UnionToIoF<U> extends { (a: infer A): void; } ? A : never;
+
+// prepend an element to a tuple.
+type Prepend<U, T extends ReadonlyArray<any>> =
+    ((a: U, ...r: T) => void) extends (...r: infer R) => void ? R : never;
+
+type UnionToTupleRecursively<Union, Result extends ReadonlyArray<any>> = {
+    1: Result;
+    0: UnionToTupleRecursively_<Union, UnionPop<Union>, Result>;
+    // 0: UnionToTupleRecursively<Exclude<Union, UnionPop<Union>>, Prepend<UnionPop<Union>, Result>>
+}[[Union] extends [never] ? 1 : 0];
+
+type UnionToTupleRecursively_<Union, Element, Result extends ReadonlyArray<any>> =
+    UnionToTupleRecursively<Exclude<Union, Element>, Prepend<Element, Result>>;
+
+type UnionToTuple<U> = UnionToTupleRecursively<U, []>;
+*/
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