email address parser

email_address_parse.yrl

% Based on RFC5321 (Simple Mail Transfer Protocol)
% https://tools.ietf.org/rfc/rfc5321.txt
% + Added support for RFC6532 via RFC6531 (SMTP Extension for Internationalized Email)
%   https://tools.ietf.org/rfc/rfc6532.txt
%   https://tools.ietf.org/rfc/rfc6531.txt

Nonterminals
    mailbox
    localpart
    domainpart
    domain
    addresslit
    addresslit_ipv6
    addresslit_ipv4
    ipv6addr
    ipv6full
    ipv6comp
    ipv6comp8
    ipv6comp7
    ipv6comp6
    ipv6comp5
    ipv6comp4
    ipv6comp3
    ipv6comp2
    ipv6comp1
    dotstring
.

Terminals
    atext
    dtext
    qstring
    snum
    ipv6pre
    ipv6hex
    '@'
    '.'
    '[' ']'
    ':' '::'
.

Rootsymbol mailbox.
Endsymbol '$end'.

% Mailbox specification

mailbox         ->   localpart '@' domainpart : {'$1', '$3'}.

% Domain specification

domainpart      -> domain      : {domain, '$1'}.
domainpart      -> addresslit  : {address, '$1'}.

domain          -> dtext '.' domain : ['$1' | '$3'].
domain          -> dtext : '$1'.

addresslit      -> '[' addresslit_ipv4 ']' : '$2'.
addresslit      -> '[' addresslit_ipv6 ']' : '$2'.
% addresslit      -> '[' addresslit_general ']'

% Local part specification

localpart       -> dotstring : '$1'.
localpart       -> qstring : '$1'.

dotstring       -> atext '.' dotstring : ['$1' | '$3'].
dotstring       -> dtext '.' dotstring : ['$1' | '$3'].
dotstring       -> atext : ['$1'].
dotstring       -> dtext : ['$1'].

% Internationalized Email Headers

% UTF8-non-ascii  =   UTF8-2 / UTF8-3 / UTF8-4

% UTF-8 Byte Sequences (https://tools.ietf.org/rfc/rfc3629.txt)

% UTF8-2          =   %xC2-DF UTF8-tail

% UTF8-3          =   %xE0 %xA0-BF UTF8-tail / %xE1-EC 2( UTF8-tail ) /
                    %xED %x80-9F UTF8-tail / %xEE-EF 2( UTF8-tail )

% UTF8-4          =   %xF0 %x90-BF 2( UTF8-tail ) / %xF1-F3 3( UTF8-tail ) /
                    %xF4 %x80-8F 2( UTF8-tail )

% UTF8-tail       =   %x80-BF

% SMTP Address Literals

% dcontent        =   %d33-90 / % Printable US-ASCII
                    %d94-126  % excl. "[", "\", "]"

addresslit_ipv4  -> snum '.' snum '.' snum '.' snum : {'$1', '$3', '$5', '$7'}.

addresslit_ipv6  -> ipv6pre ipv6addr : '$2'.

ipv6addr         -> ipv6full : '$1'.
ipv6addr         -> ipv6comp : '$1'.
% ipv6addr         -> ipv6v4full
% ipv6addr         -> ipv6v4comp

ipv6full         -> ipv6hex ':' ipv6hex ':' ipv6hex ':' ipv6hex ':' ipv6hex ':' ipv6hex ':' ipv6hex ':' ipv6hex : {'$1', '$3', '$5', '$7', '$9', '$11', '$13', '$15'}.
ipv6comp         -> ipv6comp8 : '$1'.

ipv6comp8        -> ipv6hex ':' ipv6comp7 : ['$1' | '$3'].
ipv6comp8        -> '::' ipv6comp7 : '$2'.
ipv6comp7        -> ipv6hex ':' ipv6comp6 : ['$1' | '$3'].
ipv6comp7        -> '::' ipv6comp6 : '$2'.
ipv6comp6        -> ipv6hex ':' ipv6comp5 : ['$1' | '$3'].
ipv6comp6        -> '::' ipv6comp5 : '$2'.
ipv6comp5        -> ipv6hex ':' ipv6comp4 : ['$1' | '$3'].
ipv6comp5        -> '::' ipv6comp4 : '$2'.
ipv6comp4        -> ipv6hex ':' ipv6comp3 : ['$1' | '$3'].
ipv6comp4        -> '::' ipv6comp3 : '$2'.
ipv6comp3        -> ipv6hex ':' ipv6comp2 : ['$1' | '$3'].
ipv6comp3        -> '::' ipv6comp2 : '$2'.
ipv6comp2        -> ipv6hex ':' ipv6comp1 : ['$1' | '$3'].
ipv6comp2        -> '::' ipv6comp1 : '$2'.
ipv6comp1        -> ipv6hex ':' ipv6hex : ['$1', '$3'].
ipv6comp1        -> '::' ipv6hex : ['$2'].
ipv6comp1        -> '::' : [].

% IPv6v4-full     =   IPv6-hex 5(":" IPv6-hex) ":" IPv4-address-literal

% General-address-literal  =   Standardized-tag ":" 1*dcontent

% Standardized-tag         =   Ldh-str


% IPv6v4-comp     =   [IPv6-hex *3(":" IPv6-hex)] "::"
%                     [IPv6-hex *3(":" IPv6-hex) ":"]
%                     IPv4-address-literal

email_address_scan.xrl

Definitions.

DIGIT  = [0-9]
ALPHA  = [a-zA-Z]
HEXDIG = ({DIGIT}|[A-F])
LET    = ({ALPHA}|{DIGIT})
LDH    = ({ALPHA}|{DIGIT}|-)

ATEXT = ({ALPHA}|{DIGIT}|[!#$%&'*+\-/=?^_`{|}~])

QPAIR = \[\d32-\d126]
QTEXT = [\d32-\d33\d35-\d91\d93-\d126]

IPV6PRE = IPv6:

Rules.

(::|[@:.\[\]]) :
    {token, {list_to_atom(TokenChars), TokenLine, TokenChars}}.

[12]?{DIGIT}?{DIGIT} :
    {token, {snum, TokenLine, TokenChars}}.

{HEXDIG}?{HEXDIG}?{HEXDIG}?{HEXDIG} :
    {token, {ipv6hex, TokenLine, TokenChars}}.

{LET}{LDH}*{LET} :
    {token, {dtext, TokenLine, TokenChars}}.

{ATEXT}+ :
    {token, {atext, TokenLine, TokenChars}}.

{IPV6PRE} :
    {token, {ipv6pre, TokenLine, TokenChars}}.

"({QPAIR}|{QTEXT})" :
    {token, {qstring, TokenLine, TokenChars}}.

Erlang code.