toJSON

The toJSON() function prepares a value for JSON serialization while respecting objects' toJSON methods, traversing arrays/tuples, and excluding functions.

Interactive example

Syntax

type ToJSON<GenericInput extends unknown> =
	GenericInput extends number | string | null | undefined
		? GenericInput
		: GenericInput extends { toJSON: AnyFunction }
			? ReturnType<GenericInput["toJSON"]>
			: GenericInput extends [infer InferredFirst, ...infer InferredRest]
				? [
					ToJSON<InferredFirst>,
					...(
						ToJSON<InferredRest> extends infer InferredSubRest extends any[]
							? IsEqual<InferredSubRest, never[]> extends false
								? InferredSubRest
								: []
							: []
					)
				]
				: GenericInput extends any[]
					? ToJSON<GenericInput[number]>[]
					: GenericInput extends Record<number, unknown>
						? {
							[Prop in keyof GenericInput as GenericInput[Prop] extends AnyFunction ? never : Prop]:
								ToJSON<GenericInput[Prop]>;
						}
						: undefined;

function toJSON<
	GenericInput extends unknown
>(
	input: GenericInput
): ToJSON<GenericInput>;

Parameters

• input : Value to transform into a JSON-safe structure.

Return value

A value ready for JSON serialization, with toJSON methods respected and functions excluded.

See also

• toTransform - Generic transformation via toTransform