method Node.prototype.getFirstDescendantimport { Node } from "https://dotland.deno.dev/x/fresh@1.6.7/src/dev/deps.ts"; getFirstDescendant<T extends Node>(condition?: (node: Node) => node is T): T | undefinedGets the first descendant by a condition. getFirstDescendant(condition?: (node: Node) => boolean): Node | undefinedGets the first descendant by a condition. Gets the first descendant by a condition. Type ParametersT extends NodeParametersoptionalcondition: (node: Node) => node is T Condition. ReturnsT | undefinedGets the first descendant by a condition. Parametersoptionalcondition: (node: Node) => boolean Condition. ReturnsNode | undefined