email_address

Summary

email_address is a canonical email mailbox address encoded as a single lowercase ASCII string of the form:

local-part@domain

Canonical form

An email_address value MUST:

• contain exactly one @
• be entirely lowercase ASCII
• contain a non-empty local part
• contain a non-empty domain part
• contain no surrounding whitespace

The local part MUST:

• contain only lowercase ASCII letters, digits, and these characters:

.!#$%&'*+/=?^_`{|}~-

• not begin or end with .
• not contain consecutive dots

The domain part MUST:

• consist of lowercase ASCII labels separated by .
• contain only lowercase ASCII letters, digits, -, and .
• not begin or end with .
• not contain consecutive dots
• have labels that are non-empty
• have labels that do not begin or end with -

Notes

email_address is a practical canonical mailbox form for Chronicle use. It does not attempt to represent every mailbox syntax accepted by email standards or specific providers.

This type does not define provider-specific alias normalization. In particular, it does not remove +tags, collapse dots, or apply provider-specific mailbox equivalence rules.

Examples

Valid:

• alice@example.com
• alice+news@example.com
• ops@sub.example.org
• a_b.c-d@example-mail.org

Invalid:

• Alice@example.com
• alice@example.com
• alice..bob@example.com
• .alice@example.com
• alice.@example.com
• alice@example..com
• alice@-example.com
• Alice <alice@example.com>
• mailto:alice@example.com
• alice@@example.com