#include <StringConstants.au3> ; to declare the Constants of StringRegExp
#include <Array.au3> ; UDF needed for _ArrayDisplay and _ArrayConcatenate
Local $sRegex = "((?!\[)[\d\-]+(?=\]))|((?!\[){{[\w-_]*}}=[\d-]+(?=\]))"
Local $sString = "Date format: [2017-10-27] or [{{variable-name}}=2017-10-27]" & @CRLF & _
"" & @CRLF & _
"//match the date format [YYYY-MM-DD] or [{{variable-name}}=YYYY-MM-DD] for datepicker, but filter out "Square Brackets[]" at the same time? "
Local $aArray = StringRegExp($sString, $sRegex, $STR_REGEXPARRAYGLOBALFULLMATCH)
Local $aFullArray[0]
For $i = 0 To UBound($aArray) -1
_ArrayConcatenate($aFullArray, $aArray[$i])
Next
$aArray = $aFullArray
; Present the entire match result
_ArrayDisplay($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