import Foundation
let pattern = #"^@\w+\{.*?^\}"#
let regex = try! NSRegularExpression(pattern: pattern, options: [.anchorsMatchLines, .dotMatchesLineSeparators])
let testString = #"""
@Article{Qin:2013mta,
Title = {{Practical corollaries of transverse Ward-Green-Takahashi identities}},
Author = {Qin, Si-Xue and Chang, Lei and Liu, Yu-Xin and Roberts, Craig D. and Schmidt, Sebastian M.},
Journal = {Phys.Lett.},
Year = {2013},
Pages = {384-388},
Volume = {B722},
Archiveprefix = {arXiv},
Bdsk-url-1 = {http://dx.doi.org/10.1016/j.physletb.2013.04.034},
Doi = {10.1016/j.physletb.2013.04.034},
Eprint = {1302.3276},
Primaryclass = {nucl-th},
Slaccitation = {%%CITATION = ARXIV:1302.3276;%%}
}
@Article{Qin:2011xq,
Title = {{Investigation of rainbow-ladder truncation for excited and exotic mesons}},
Author = {Qin, Si-xue and Chang, Lei and Liu, Yu-xin and Roberts, Craig D. and Wilson, David J.},
Journal = {Phys.Rev.},
Year = {2012},
Pages = {035202},
Volume = {C85},
Archiveprefix = {arXiv},
Bdsk-url-1 = {http://dx.doi.org/10.1103/PhysRevC.85.035202},
Doi = {10.1103/PhysRevC.85.035202},
Eprint = {1109.3459},
Primaryclass = {nucl-th},
Slaccitation = {%%CITATION = ARXIV:1109.3459;%%}
}
@Article{Qin:2011dd,
Title = {{Interaction model for the gap equation}},
Author = {Qin, Si-xue and Chang, Lei and Liu, Yu-xin and Roberts, Craig D. and Wilson, David J.},
Journal = {Phys.Rev.},
Year = {2011},
Pages = {042202},
Volume = {C84},
Archiveprefix = {arXiv},
Bdsk-url-1 = {http://dx.doi.org/10.1103/PhysRevC.84.042202},
Doi = {10.1103/PhysRevC.84.042202},
Eprint = {1108.0603},
Primaryclass = {nucl-th},
Slaccitation = {%%CITATION = ARXIV:1108.0603;%%}
}
@Article{Qin:2013ufa,
Title = {{Quark Spectral Function and Deconfinement at Nonzero Temperature}},
Author = {Qin, Si-xue and Rischke, Dirk H.},
Journal = {Phys.Rev.},
Year = {2013},
Pages = {056007},
Volume = {D88},
Archiveprefix = {arXiv},
Bdsk-url-1 = {http://dx.doi.org/10.1103/PhysRevD.88.056007},
Doi = {10.1103/PhysRevD.88.056007},
Eprint = {1304.6547},
Primaryclass = {nucl-th},
Slaccitation = {%%CITATION = ARXIV:1304.6547;%%}
}
"""#
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