 private let swiftImplicitParameterStart: Character = "$"
 
 private let swiftIdentifierStartCharacters =
-    swiftIdentifierStartCharacters1 +
-    swiftIdentifierStartCharacters2 +
-    swiftIdentifierStartCharacters3 +
-    swiftIdentifierStartCharacters4
-
-// Split declaration of swiftIdentifierStartCharacter because "Expression was
-// too complex to be solved in reasonable time; consider breaking up the
-// expression into distinct sub-expressions" error.
-private let swiftIdentifierStartCharacters1 =
     (0x0041...0x005A).stringValue + // 'A' to 'Z'
     (0x0061...0x007A).stringValue + // 'a' to 'z'
     "_" +

    (0xFD40...0xFDCF).stringValue +
    (0xFDF0...0xFE1F).stringValue +
    (0xFE30...0xFE44).stringValue +
    (0xFE47...0xFFFD).stringValue

private let swiftIdentifierStartCharacters4 =
    (0x10000...0x1FFFD).stringValue +
    (0x20000...0x2FFFD).stringValue +
    (0x30000...0x3FFFD).stringValue +

    (0x0370...0x167F).stringValue +
    (0x1681...0x180D).stringValue +
    (0x180F...0x1DBF).stringValue +
    (0x1E00...0x1FFF).stringValue +
    (0x200B...0x200D).stringValue +
    (0x202A...0x202E).stringValue +
    (0x203F...0x2040).stringValue +
