#include <StringConstants.au3> ; to declare the Constants of StringRegExp
#include <Array.au3> ; UDF needed for _ArrayDisplay and _ArrayConcatenate
Local $sRegex = "(?iu)^(?<localPart>(?<dotString>[0-9a-z!#$%&'*+-\/=?^_`\{|\}~\u{80}-\u{10FFFF}]+(\.[0-9a-z!#$%&'*+-\/=?^_`\{|\}~\u{80}-\u{10FFFF}]+)*)|(?<quotedString>"([\x20-\x21\x23-\x5B\x5D-\x7E\u{80}-\u{10FFFF}]|\\[\x20-\x7E])*"))(?<!.{64,})@(?<domainOrAddressLiteral>(?<addressLiteral>\[((?<IPv4>\d{1,3}(\.\d{1,3}){3})|(?<IPv6Full>IPv6:[0-9a-f]{1,4}(:[0-9a-f]{1,4}){7})|(?<IPv6Comp>IPv6:([0-9a-f]{1,4}(:[0-9a-f]{1,4}){0,5})?::([0-9a-f]{1,4}(:[0-9a-f]{1,4}){0,5})?)|(?<IPv6v4Full>IPv6:[0-9a-f]{1,4}(:[0-9a-f]{1,4}){5}:\d{1,3}(\.\d{1,3}){3})|(?<IPv6v4Comp>IPv6:([0-9a-f]{1,4}(:[0-9a-f]{1,4}){0,3})?::([0-9a-f]{1,4}(:[0-9a-f]{1,4}){0,3}:)?\d{1,3}(\.\d{1,3}){3})|(?<generalAddressLiteral>[a-z0-9-]*[[a-z0-9]:[\x21-\x5A\x5E-\x7E]+))\])|(?<Domain>(?!.{64,})(([0-9a-z\u{80}-\u{10FFFF}]([0-9a-z-\u{80}-\u{10FFFF}]*[0-9a-z\u{80}-\u{10FFFF}])?))(\.([0-9a-z\u{80}-\u{10FFFF}]([0-9a-z-\u{80}-\u{10FFFF}]*[0-9a-z\u{80}-\u{10FFFF}])?))*))$"
Local $sString = "postmaster@[123.123.32.245]"
Local $aArray = StringRegExp($sString, $sRegex, $STR_REGEXPARRAYFULLMATCH)
; Present the entire match result
_ArrayDisplay($aArray, "Result")
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for AutoIt, please visit: https://www.autoitscript.com/autoit3/docs/functions/StringRegExp.htm