import Foundation
let pattern = #"\((?:[^()]++|(?R))*\)"#
let regex = try! NSRegularExpression(pattern: pattern, options: .anchorsMatchLines)
let testString = #"""
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."
----------
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.
"""#
let stringRange = NSRange(location: 0, length: testString.utf16.count)
let matches = regex.matches(in: testString, range: stringRange)
var result: [[String]] = []
for match in matches {
var groups: [String] = []
for rangeIndex in 1 ..< match.numberOfRanges {
let nsRange = match.range(at: rangeIndex)
guard !NSEqualRanges(nsRange, NSMakeRange(NSNotFound, 0)) else { continue }
let string = (testString as NSString).substring(with: nsRange)
groups.append(string)
}
if !groups.isEmpty {
result.append(groups)
}
}
print(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 Swift 5.2, please visit: https://developer.apple.com/documentation/foundation/nsregularexpression