```js
// @noErrors
import { defineParams } from '@sveltejs/kit/params';
```

## defineParams

Define [parameter matchers](/docs/kit/advanced-routing#Matching) for your app.

<div class="ts-block">

```dts
function defineParams<
	T extends Record<string, ParamDefinition>
>(definitions: T): DefinedParams<T>;
```

</div>



## DefinedParams

The return type of [`defineParams`](/docs/kit/@sveltejs-kit-params#defineParams).

<div class="ts-block">

```dts
type DefinedParams<
	T extends Record<string, ParamDefinition>
> = {
	readonly [K in keyof T]: ParamEntry<T[K]>;
};
```

</div>

## MatcherParam

Extracts the param type from a matcher.

<div class="ts-block">

```dts
type MatcherParam<M extends StandardSchemaV1<any, any>> =
	M extends StandardSchemaV1<any, infer Inner>
		? Inner extends ParamValue
			? Inner
			: Inner extends StandardSchemaV1<any, any>
				? StandardSchemaV1.InferOutput<Inner> extends ParamValue
					? StandardSchemaV1.InferOutput<Inner>
					: never
				: never
		: never;
```

</div>

## ParamDefinition

A param matcher definition passed to [`defineParams`](/docs/kit/@sveltejs-kit-params#defineParams).

<div class="ts-block">

```dts
type ParamDefinition =
	| ((param: string) => ParamValue | undefined)
	| StandardSchemaV1<string, ParamValue>;
```

</div>

## ParamMatcher

The shape of a param matcher. See [matching](/docs/kit/advanced-routing#Matching) for more info.

<div class="ts-block">

```dts
type ParamMatcher<Output = any> = StandardSchemaV1<
	string,
	Output
>;
```

</div>

## ParamValue

A value that can be parsed from a URL param and losslessly encoded with `String(...)`.

<div class="ts-block">

```dts
type ParamValue = string | number | boolean | bigint;
```

</div>