import type { registerMap } from "echarts/core"; type GeoJSONInput = Parameters[1]; type FeatureCollectionLike = { type?: unknown }; export function isGeoJSONSource(value: unknown): value is GeoJSONInput { if (typeof value === "string") { return true; } if (value && typeof value === "object" && "type" in value) { const type = (value as FeatureCollectionLike).type; return type === "FeatureCollection"; } return false; }