--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/3rdparty/maddy/quoteparser.h	Tue Aug 17 11:19:54 2021 +0200
@@ -0,0 +1,165 @@
+/*
+ * This project is licensed under the MIT license. For more information see the
+ * LICENSE file.
+ */
+#pragma once
+
+// -----------------------------------------------------------------------------
+
+#include <functional>
+#include <regex>
+#include <string>
+
+#include "maddy/blockparser.h"
+
+// -----------------------------------------------------------------------------
+
+namespace maddy {
+
+// -----------------------------------------------------------------------------
+
+/**
+ * QuoteParser
+ *
+ * @class
+ */
+class QuoteParser : public BlockParser
+{
+public:
+  /**
+   * ctor
+   *
+   * @method
+   * @param {std::function<void(std::string&)>} parseLineCallback
+   * @param {std::function<std::shared_ptr<BlockParser>(const std::string& line)>} getBlockParserForLineCallback
+   */
+   QuoteParser(
+    std::function<void(std::string&)> parseLineCallback,
+    std::function<std::shared_ptr<BlockParser>(const std::string& line)> getBlockParserForLineCallback
+  )
+    : BlockParser(parseLineCallback, getBlockParserForLineCallback)
+    , isStarted(false)
+    , isFinished(false)
+  {}
+
+  /**
+   * IsStartingLine
+   *
+   * A quote starts with `> `.
+   *
+   * @method
+   * @param {const std::string&} line
+   * @return {bool}
+   */
+  static bool
+  IsStartingLine(const std::string& line)
+  {
+    static std::regex re("^\\>.*");
+    return std::regex_match(line, re);
+  }
+
+  /**
+   * AddLine
+   *
+   * Adding a line which has to be parsed.
+   *
+   * @method
+   * @param {std::string&} line
+   * @return {void}
+   */
+  void
+  AddLine(std::string& line) override
+  {
+    if (!this->isStarted)
+    {
+      this->result << "<blockquote>";
+      this->isStarted = true;
+    }
+
+    bool finish = false;
+    if (line.empty())
+    {
+      finish = true;
+    }
+
+    this->parseBlock(line);
+
+    if (this->isInlineBlockAllowed() && !this->childParser)
+    {
+      this->childParser = this->getBlockParserForLine(line);
+    }
+
+    if (this->childParser)
+    {
+      this->childParser->AddLine(line);
+
+      if (this->childParser->IsFinished())
+      {
+        this->result << this->childParser->GetResult().str();
+        this->childParser = nullptr;
+      }
+
+      return;
+    }
+
+    if (this->isLineParserAllowed())
+    {
+      this->parseLine(line);
+    }
+
+    if (finish)
+    {
+      this->result << "</blockquote>";
+      this->isFinished = true;
+    }
+
+    this->result << line;
+  }
+
+  /**
+   * IsFinished
+   *
+   * @method
+   * @return {bool}
+   */
+  bool
+  IsFinished() const override
+  {
+    return this->isFinished;
+  }
+
+protected:
+  bool
+  isInlineBlockAllowed() const override
+  {
+    return true;
+  }
+
+  bool
+  isLineParserAllowed() const override
+  {
+    return true;
+  }
+
+  void
+  parseBlock(std::string& line) override
+  {
+    static std::regex lineRegexWithSpace("^\\> ");
+    line = std::regex_replace(line, lineRegexWithSpace, "");
+    static std::regex lineRegexWithoutSpace("^\\>");
+    line = std::regex_replace(line, lineRegexWithoutSpace, "");
+
+    if (!line.empty())
+    {
+      line += " ";
+    }
+  }
+
+private:
+  bool isStarted;
+  bool isFinished;
+}; // class QuoteParser
+
+// -----------------------------------------------------------------------------
+
+} // namespace maddy