$re = '/\((?:[^()]++|(?R))*\)|,/m';
$str = 'SELECT Name AS [Object Name], Switch([Type]=5,\'Query\',[Type]=-32768,\'Form\',[Type]=6,\'Table\') AS [Object Type], Switch([Type]=5,1,[Type]=-32768,2,[Type] In (1,4,6),6) AS [Object Type ID], Left(Name,4) as Prefix, LTrim(RTrim(Mid([Name],5,30))) as Suffix
SELECT "Amy\'s code is righteous.", left("abc",1), right(\'source code\',4), "Bill\'s code has been righteous too."
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End goal is to replace all commas in SQL SELECT clause with comma+linefeed but ignore commas inside parenthesis (which may be nested).
\\((?:[^()]++|(?R))*\\)
This expression will find all of the nested parentheis using recursion. I want to do one of these two options:
a) Replace all commas in the matched groups with the pipe "|" character,
then with two simple StrReplace() calls: replace all commas with comma+linefeed, then replace all | with comma.
OR
b) Select all text that is not in the matched group and replace commas with comma+linefeed.
I\'m using AutoHotkey and the RegExReplace() function.';
$subst = "|$0|";
$result = preg_replace($re, $subst, $str);
echo "The result of the substitution is ".$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 PHP, please visit: http://php.net/manual/en/ref.pcre.php