//! WHOIS Domain and IP Registry Query Protocol (RFC 3912) Layer 7 AST definitions.
//!
//! This module defines the abstract syntax tree (AST) configuration parameters for synthesizing
//! WHOIS Domain and IP Registry Query Protocol packets over TCP port 43. On the wire, the protocol uses a Cleartext TCP query-response transaction on port 43 where the client transmits a CRLF-terminated domain name, Autonomous System Number (ASN), or IPv4/IPv6 CIDR prefix query (`<domain>\r\n`) and the RIR/TLD registry server returns human-readable key-value lines (`Domain Name:`, `Registrar:`, `Updated Date:`) before closing the connection.
//! Every field in [`WhoisSpec`] is optional so authors can emit zero-configuration default
//! frames or override specific protocol header fields and attributes.
//!
//! Canonical `.fasm` syntax:
//! `a -> b WHOIS [QUERY | RESPONSE] [DOMAIN <str>] [REGISTRAR <str>]`
/// RFC 3912 WHOIS Protocol specification.
///
/// Syntax mapping: `WHOIS [QUERY | RESPONSE] [DOMAIN <str>] [REGISTRAR <str>]`
#[doc(alias = "WHOIS")]
#[doc(alias = "RFC 3912")]
#[doc(alias = "RFC3912")]
#[doc(alias = "QUERY")]
#[doc(alias = "RESPONSE")]
#[doc(alias = "DOMAIN")]
#[doc(alias = "REGISTRAR")]
#[derive(Debug, Clone, PartialEq, Eq, Default)]
pub struct WhoisSpec<'a> {
/// Query flag.
pub is_query: bool,
/// Response flag.
pub is_response: bool,
/// Domain query string.
pub domain: Option<&'a str>,
/// Registrar description string.
pub registrar: Option<&'a str>,
}