# Simplify

**Kind:** Type

**Source:** [`src/utils/types.ts`](https://github.com/honojs/hono/blob/main/src/utils/types.ts#L93)

**Part of:** [Utils](subsystem-src-utils)

Useful to flatten the type output to improve type hints shown in editors. And also to transform an interface into a type to aide with assignability.

`Simplify<T>` remaps the properties of `T` into a plain object type, which makes expanded type hints easier to read in editors. It can also convert an interface-shaped type into a type alias shape for assignability checks.

## Definition

```ts
{ [KeyType in keyof T]: T[KeyType] } & {}
```

## Diagram

```mermaid
graph LR
  A[Input type T] --> B[Simplify<T>]
  B --> C[Remapped object properties]
  C --> D[Clearer editor type hints]
  C --> E[Type alias assignability]
```

## Usage

```ts
type Simplify<T> = {
  [Key in keyof T]: T[Key];
};

interface User {
  id: string;
  name: string;
}

type UserRecord = Simplify<User>;

const user: UserRecord = {
  id: "user_123",
  name: "Ada",
};
```

## AI Coding Instructions

- Apply `Simplify<T>` when an intersection or mapped type produces hard-to-read editor hints.
- Keep `Simplify` type-only; it does not transform values at runtime.
- Use it near public type boundaries where consumers benefit from a remapped object shape.
- Do not expect `Simplify<T>` to change property values, optionality, or readonly modifiers.