 
 private extension Dictionary where Key == SyntaxType, Value == [NSRange] {
     
-    /// Remove duplicated ranges.
+    /// Remove overlapped ranges.
     ///
     /// - Note:
     /// This sanitization reduces the performance time of `SyntaxParser.apply(highlights:range:)` significantly.

//  ---------------------------------------------------------------------------
//
//  © 2004-2007 nakamuxu
//  © 2014-2019 1024jp
//
//  Licensed under the Apache License, Version 2.0 (the "License");
//  you may not use this file except in compliance with the License.

    /// so we want to remove useless highlighting ranges as many as possible beforehand.
    ///
    /// - Returns: Sanitized syntax highlight dictionary.
    func sanitized() -> Self {
        
        var registeredIndexes = IndexSet()
        
