Function: extractRouteParams()

API / @xmachines/play-router / extractRouteParams

function extractRouteParams(pathname, pattern): Record<string, string>;

Defined in: router-sync.ts:112

Extract named path parameters from a URL using the URLPattern API.

Takes the pattern string directly — use this when the pattern is already known. For extraction via a state ID lookup, see RouterBridgeBase.extractParams.

Undefined values (unmatched optional segments, e.g. /settings against /settings/:section?) are omitted from the returned object.

The pattern is normalized with the same rules RouteMap uses for matching (hyphenated names like :cat-id become :cat_id for URLPattern), and the extracted group names are mapped back to the original param names, so /docs/123 against /docs/:cat-id yields { "cat-id": "123" }.

Values are percent-decoded (john%20doe → john doe), matching framework router semantics (e.g. vue-router). Malformed sequences are kept raw.

Parameters

Parameter	Type	Description
pathname	string	The concrete URL pathname (e.g. /profile/alice)
pattern	string	The URL pattern template (e.g. /profile/:username)

Returns

Record<string, string>

A record of extracted parameter values, or {} for static patterns.

Throws

When URLPattern is absent and the pattern is parameterized.

Example

import { extractRouteParams } from "@xmachines/play-router";

extractRouteParams("/profile/alice", "/profile/:username");
// → { username: "alice" }

extractRouteParams("/settings", "/settings/:section?");
// → {}  (optional param absent — not included)