react-querybuilder/dist/types-esm/types/type-fest/writable.d.mts

React Query Builder component for constructing queries and filters, with utilities for executing them in various database and evaluation contexts

import type { Except } from "./except.mjs";
import type { Simplify } from "./simplify.mjs";
/**
Create a writable version of the given array type.
*/
type WritableArray<ArrayType extends readonly unknown[]> = ArrayType extends readonly [] ? [] : ArrayType extends readonly [...infer U, infer V] ? [...U, V] : ArrayType extends readonly [infer U, ...infer V] ? [U, ...V] : ArrayType extends ReadonlyArray<infer U> ? U[] : ArrayType;
/**
Create a type that strips `readonly` from the given type. Inverse of `Readonly<T>`.

The 2nd argument will be ignored if the input type is not an object.

Note: This type can make readonly `Set` and `Map` writable. This behavior is different from `Readonly<T>` (as of TypeScript 5.2.2). See: https://github.com/microsoft/TypeScript/issues/29655

This can be used to [store and mutate options within a class](https://github.com/sindresorhus/pageres/blob/4a5d05fca19a5fbd2f53842cbf3eb7b1b63bddd2/source/index.ts#L72), [edit `readonly` objects within tests](https://stackoverflow.com/questions/50703834), [construct a `readonly` object within a function](https://github.com/Microsoft/TypeScript/issues/24509), or to define a single model where the only thing that changes is whether or not some of the keys are writable.

@example
```
import type {Writable} from 'type-fest';

type Foo = {
readonly a: number;
readonly b: readonly string[]; // To show that only the mutability status of the properties, not their values, are affected.
readonly c: boolean;
};

const writableFoo: Writable<Foo> = {a: 1, b: ['2'], c: true};
writableFoo.a = 3;
writableFoo.b[0] = 'new value'; // Will still fail as the value of property "b" is still a readonly type.
writableFoo.b = ['something']; // Will work as the "b" property itself is no longer readonly.

type SomeWritable = Writable<Foo, 'b' | 'c'>;
// type SomeWritable = {
// 	readonly a: number;
// 	b: readonly string[]; // It's now writable. The type of the property remains unaffected.
// 	c: boolean; // It's now writable.
// }

// Also supports array
const readonlyArray: readonly number[] = [1, 2, 3];
readonlyArray.push(4); // Will fail as the array itself is readonly.
const writableArray: Writable<typeof readonlyArray> = readonlyArray as Writable<typeof readonlyArray>;
writableArray.push(4); // Will work as the array itself is now writable.
```

@group type-fest
*/
export type Writable<
	BaseType,
	Keys extends keyof BaseType = keyof BaseType
> = BaseType extends ReadonlyMap<infer KeyType, infer ValueType> ? Map<KeyType, ValueType> : BaseType extends ReadonlySet<infer ItemType> ? Set<ItemType> : BaseType extends readonly unknown[] ? WritableArray<BaseType> : Simplify<Except<BaseType, Keys> & { -readonly [KeyType in keyof Pick<BaseType, Keys>] : Pick<BaseType, Keys>[KeyType] }>;
export {};