export type Acct = { username: string; host: string | null; }; export function parse(acct: string): Acct { if (acct.startsWith('@')) acct = acct.substring(1); const split = acct.split('@', 2); return { username: split[0], host: split[1] ?? null }; } export function toString(acct: Acct): string { return acct.host == null ? acct.username : `${acct.username}@${acct.host}`; }