import type { AssetFields } from './__generated__/AssetFields'; export interface ERC20Asset extends AssetFields { source: { __typename: 'ERC20'; contractAddress: string; }; } // Type guard to ensure an asset is an ERC20 token export const isERC20Asset = (asset: AssetFields): asset is ERC20Asset => { if (asset.source.__typename === 'ERC20') { return true; } return false; };