@burglekitt/gmt/dist/regex/rfc-2822.js

Temporal-based date and time utilities with timezone support and polyfill integration

// RFC 5322 §3.3 date-time grammar (obsoletes RFC 2822, same date-time shape).
// English day/month names are mandated by the spec regardless of locale — see
// `internal/englishCalendarNames.ts`. Day is `1*2DIGIT` per the formal
// grammar, so single-digit days are valid on input even though GMT's own
// formatter always emits the zero-padded 2-digit form. `zone` accepts a
// numeric offset or one of the obsolete named zones RFC 5322 §4.3 lists
// (UT/GMT plus the eight North American zones); any other obs-zone letter is
// unrecognized and treated as invalid rather than guessed at.
export const rfc2822DateTime = /^(?:(Mon|Tue|Wed|Thu|Fri|Sat|Sun), )?(\d{1,2}) (Jan|Feb|Mar|Apr|May|Jun|Jul|Aug|Sep|Oct|Nov|Dec) (\d{4}) (\d{2}):(\d{2})(?::(\d{2}))? (UT|GMT|EST|EDT|CST|CDT|MST|MDT|PST|PDT|[+-]\d{4})$/;