Function assertNodeType

src/parseNode.ts:9–20

(
    node: AnyParseNode | null | undefined,
    type: NODETYPE,
)

 * typing. Throws if the node's type does not match.
 */
export function assertNodeType<NODETYPE extends NodeType>(
    node: AnyParseNode | null | undefined,
    type: NODETYPE,
): ParseNode<NODETYPE> {
    if (!node || node.type !== type) {
        throw new Error(
            `Expected node of type ${type}, but got ` +
            (node ? `node of type ${node.type}` : String(node)));
    }

    return node as ParseNode<NODETYPE>;
}

/**
 * Returns the node more strictly typed iff it is of the given type. Otherwise,