import Foundation
let pattern = #"""
^\h*
(?<linetype>[0123456])\h+
(?<color> (?&Number) )\h+
(?<xrot> (?&Number) )\h+ (?<yrot> (?&Number) )\h+ (?<zrot> (?&Number) )\h+
(?<xpos> (?&Number) )\h+ (?<ypos> (?&Number) )\h+ (?<zpos> (?&Number) )\h+
(?<xcam> (?&Number) )\h+ (?<ycam> (?&Number) )\h+ (?<zcam> (?&Number) )\h+
(?<xsca> (?&Number) )\h+ (?<ysca> (?&Number) )\h+ (?<zsca> (?&Number) )\h+
(?<filename>\S+[.]\S+)
$
(?(DEFINE)
(?<Number> [-]? \d+ (?> [.]\d* )? (?> [Ee] [+-]? \d+ )? )
)
"""#
let regex = try! NSRegularExpression(pattern: pattern, options: [.anchorsMatchLines, .allowCommentsAndWhitespace])
let testString = ##"""
1 0 0 0 0 1 0 0 0 1 0 0 0 1 3024.dat
#linetype color XROT YROY ZROT XPOS YPOS ZPOS XCAM YCAM ZCAM XSCA YSCA ZSCA FILE
"""##
let stringRange = NSRange(location: 0, length: testString.utf16.count)
let substitutionString = #"${linetype} ${color} ($xrot,$yrot,$zrot) {$xpos,$ypos,$zpos} <$xcam,$ycam,$zcam> [$xsca,$ysca,$zsca] "$filename""#
let result = regex.stringByReplacingMatches(in: testString, range: stringRange, withTemplate: substitutionString)
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