diff --git a/src/Parser/Parsing/IParserLineStream.cpp b/src/Parser/Parsing/IParserLineStream.cpp
index 332e6302..60ba91c0 100644
--- a/src/Parser/Parsing/IParserLineStream.cpp
+++ b/src/Parser/Parsing/IParserLineStream.cpp
@@ -1,15 +1,12 @@
 #include "IParserLineStream.h"
 
-const std::string ParserLine::EMPTY_STRING;
-
 ParserLine::ParserLine()
-    : m_filename(EMPTY_STRING),
-      m_line_number(0)
+    : m_line_number(0)
 {
 }
 
-ParserLine::ParserLine(const std::string& filename, const int lineNumber, std::string line)
-    : m_filename(filename),
+ParserLine::ParserLine(std::shared_ptr<std::string> filename, const int lineNumber, std::string line)
+    : m_filename(std::move(filename)),
       m_line_number(lineNumber),
       m_line(std::move(line))
 {
diff --git a/src/Parser/Parsing/IParserLineStream.h b/src/Parser/Parsing/IParserLineStream.h
index 87a968aa..f00a3432 100644
--- a/src/Parser/Parsing/IParserLineStream.h
+++ b/src/Parser/Parsing/IParserLineStream.h
@@ -2,20 +2,19 @@
 
 #include <string>
 #include <functional>
+#include <memory>
 
 #include "Utils/ClassUtils.h"
 
 class ParserLine
 {
-    static const std::string EMPTY_STRING;
-
 public:
-    std::reference_wrapper<const std::string> m_filename;
+    std::shared_ptr<std::string> m_filename;
     int m_line_number;
     std::string m_line;
 
     ParserLine();
-    ParserLine(const std::string& filename, int lineNumber, std::string line);
+    ParserLine(std::shared_ptr<std::string> filename, int lineNumber, std::string line);
 
     _NODISCARD bool IsEof() const;
 };
diff --git a/src/Parser/Parsing/Impl/AbstractDirectiveStreamProxy.cpp b/src/Parser/Parsing/Impl/AbstractDirectiveStreamProxy.cpp
index 617849f4..492ecbd9 100644
--- a/src/Parser/Parsing/Impl/AbstractDirectiveStreamProxy.cpp
+++ b/src/Parser/Parsing/Impl/AbstractDirectiveStreamProxy.cpp
@@ -2,7 +2,7 @@
 
 TokenPos AbstractDirectiveStreamProxy::CreatePos(const ParserLine& line, const unsigned position)
 {
-    return TokenPos(line.m_filename.get(), line.m_line_number, static_cast<int>(position + 1));
+    return TokenPos(*line.m_filename, line.m_line_number, static_cast<int>(position + 1));
 }
 
 bool AbstractDirectiveStreamProxy::SkipWhitespace(const ParserLine& line, unsigned& position)
diff --git a/src/Parser/Parsing/Impl/AbstractLexer.h b/src/Parser/Parsing/Impl/AbstractLexer.h
index abd830b6..90ada5aa 100644
--- a/src/Parser/Parsing/Impl/AbstractLexer.h
+++ b/src/Parser/Parsing/Impl/AbstractLexer.h
@@ -100,7 +100,7 @@ protected:
     _NODISCARD TokenPos GetPreviousCharacterPos() const
     {
         const auto& currentLine = CurrentLine();
-        return TokenPos(currentLine.m_filename, currentLine.m_line_number, m_current_line_offset);
+        return TokenPos(*currentLine.m_filename, currentLine.m_line_number, m_current_line_offset);
     }
 
     _NODISCARD TokenPos GetNextCharacterPos()
@@ -109,10 +109,10 @@ protected:
         if (m_current_line_offset + 1 >= currentLine.m_line.size())
         {
             PeekChar();
-            return TokenPos(m_line_cache.back().m_filename, m_line_cache.back().m_line_number, 1);
+            return TokenPos(*m_line_cache.back().m_filename, m_line_cache.back().m_line_number, 1);
         }
 
-        return TokenPos(currentLine.m_filename, currentLine.m_line_number, m_current_line_offset + 1);
+        return TokenPos(*currentLine.m_filename, currentLine.m_line_number, m_current_line_offset + 1);
     }
 
     /**
@@ -155,7 +155,7 @@ protected:
         while (true)
         {
             if (m_current_line_offset >= lineSize)
-                throw ParsingException(TokenPos(currentLine.m_filename, currentLine.m_line_number, m_current_line_offset), "Unclosed string");
+                throw ParsingException(TokenPos(*currentLine.m_filename, currentLine.m_line_number, m_current_line_offset), "Unclosed string");
 
             if (currentLine.m_line[m_current_line_offset] == '\"')
                 break;
@@ -189,7 +189,7 @@ protected:
         auto exponent = false;
 
         if (*currentCharacter == '-' || *currentCharacter == '+')
-            currentCharacter++;
+            ++currentCharacter;
 
         while (*currentCharacter)
         {
@@ -208,7 +208,7 @@ protected:
                 if (exponent)
                     throw ParsingException(GetPreviousCharacterPos(), "Invalid number");
                 if (currentCharacter[1] == '-')
-                    currentCharacter++;
+                    ++currentCharacter;
                 exponent = true;
                 isInteger = false;
             }
@@ -221,7 +221,7 @@ protected:
                 break;
             }
 
-            currentCharacter++;
+            ++currentCharacter;
         }
 
         return isInteger;
@@ -290,7 +290,6 @@ protected:
 public:
     const TokenType& GetToken(unsigned index) override
     {
-        assert(index >= 0);
         while (index >= m_token_cache.size())
             m_token_cache.emplace_back(GetNextToken());
 
@@ -307,7 +306,7 @@ public:
             const auto& lastToken = m_token_cache.back();
             while (!m_line_cache.empty()
                 && (m_line_cache.front().m_line_number != lastToken.GetPos().m_line
-                    || m_line_cache.front().m_filename.get() != lastToken.GetPos().m_filename.get()))
+                    || *m_line_cache.front().m_filename != lastToken.GetPos().m_filename.get()))
             {
                 m_line_cache.pop_front();
                 m_line_index--;
@@ -319,7 +318,7 @@ public:
             m_token_cache.erase(m_token_cache.begin(), m_token_cache.begin() + amount);
             const auto& firstToken = m_token_cache.front();
             while (m_line_cache.front().m_line_number != firstToken.GetPos().m_line
-                || m_line_cache.front().m_filename.get() != firstToken.GetPos().m_filename.get())
+                || *m_line_cache.front().m_filename != firstToken.GetPos().m_filename.get())
             {
                 m_line_cache.pop_front();
                 m_line_index--;
@@ -341,7 +340,7 @@ public:
     {
         for (const auto& line : m_line_cache)
         {
-            if (line.m_filename.get() == pos.m_filename.get()
+            if (*line.m_filename == pos.m_filename.get()
                 && line.m_line_number == pos.m_line)
                 return line;
         }
diff --git a/src/Parser/Parsing/Impl/IncludingStreamProxy.cpp b/src/Parser/Parsing/Impl/IncludingStreamProxy.cpp
index d70a52fd..bd1b38c8 100644
--- a/src/Parser/Parsing/Impl/IncludingStreamProxy.cpp
+++ b/src/Parser/Parsing/Impl/IncludingStreamProxy.cpp
@@ -70,7 +70,7 @@ bool IncludingStreamProxy::MatchIncludeDirective(const ParserLine& line, const u
     unsigned filenameStart, filenameEnd;
 
     if (!ExtractIncludeFilename(line, currentPos, filenameStart, filenameEnd))
-        throw ParsingException(TokenPos(line.m_filename, line.m_line_number, static_cast<int>(currentPos)), INCLUDE_QUOTES_ERROR);
+        throw ParsingException(TokenPos(*line.m_filename, line.m_line_number, static_cast<int>(currentPos)), INCLUDE_QUOTES_ERROR);
 
     if (filenameEnd <= filenameStart)
         throw ParsingException(CreatePos(line, currentPos), "No filename specified");
@@ -103,7 +103,7 @@ bool IncludingStreamProxy::MatchPragmaOnceDirective(const ParserLine& line, cons
     if (!MatchString(line, currentPos, ONCE_PRAGMA_COMMAND, std::char_traits<char>::length(ONCE_PRAGMA_COMMAND)))
         return false;
 
-    const auto absolutePath = absolute(fs::path(line.m_filename.get()));
+    const auto absolutePath = absolute(fs::path(*line.m_filename));
     const auto absolutePathStr = absolutePath.string();
 
     const auto existingPath = m_included_files.find(absolutePathStr);
diff --git a/src/Parser/Parsing/Impl/IncludingStreamProxy.h b/src/Parser/Parsing/Impl/IncludingStreamProxy.h
index d1f22cc8..6fb64587 100644
--- a/src/Parser/Parsing/Impl/IncludingStreamProxy.h
+++ b/src/Parser/Parsing/Impl/IncludingStreamProxy.h
@@ -15,7 +15,7 @@ class IncludingStreamProxy final : public AbstractDirectiveStreamProxy
     IParserLineStream* const m_stream;
     std::set<std::string> m_included_files;
     
-    _NODISCARD static bool ExtractIncludeFilename(const ParserLine& line, unsigned includeDirectivePosition, unsigned& directiveStartPos, unsigned& filenameEndPos);
+    _NODISCARD static bool ExtractIncludeFilename(const ParserLine& line, unsigned includeDirectivePosition, unsigned& filenameStartPosition, unsigned& filenameEndPosition);
     _NODISCARD bool MatchIncludeDirective(const ParserLine& line, unsigned directiveStartPos, unsigned directiveEndPos) const;
     _NODISCARD bool MatchPragmaOnceDirective(const ParserLine& line, unsigned directiveStartPos, unsigned directiveEndPos);
     _NODISCARD bool MatchDirectives(const ParserLine& line);
diff --git a/src/Parser/Parsing/Impl/PackDefinitionStreamProxy.h b/src/Parser/Parsing/Impl/PackDefinitionStreamProxy.h
index 06404a0f..9dce21eb 100644
--- a/src/Parser/Parsing/Impl/PackDefinitionStreamProxy.h
+++ b/src/Parser/Parsing/Impl/PackDefinitionStreamProxy.h
@@ -2,6 +2,7 @@
 
 #include <stack>
 
+#include "Utils/ClassUtils.h"
 #include "AbstractDirectiveStreamProxy.h"
 #include "Parsing/IPackValueSupplier.h"
 #include "Parsing/IParserLineStream.h"
@@ -32,5 +33,5 @@ public:
     _NODISCARD bool IsOpen() const override;
     _NODISCARD bool Eof() const override;
 
-    int GetCurrentPack() const override;
+    _NODISCARD int GetCurrentPack() const override;
 };
diff --git a/src/Parser/Parsing/Impl/ParserFilesystemStream.cpp b/src/Parser/Parsing/Impl/ParserFilesystemStream.cpp
index a7569dcf..8192533e 100644
--- a/src/Parser/Parsing/Impl/ParserFilesystemStream.cpp
+++ b/src/Parser/Parsing/Impl/ParserFilesystemStream.cpp
@@ -6,13 +6,13 @@
 namespace fs = std::filesystem;
 
 ParserFilesystemStream::FileInfo::FileInfo(std::string filePath)
-    : m_file_path(std::move(filePath)),
-      m_stream(m_file_path),
+    : m_file_path(std::make_shared<std::string>(std::move(filePath))),
+      m_stream(*m_file_path),
       m_line_number(1)
 {
 }
 
-ParserFilesystemStream::ParserFilesystemStream(std::string path)
+ParserFilesystemStream::ParserFilesystemStream(const std::string& path)
 {
     const auto absolutePath = absolute(fs::path(path));
     m_files.emplace(FileInfo(absolutePath.string()));
@@ -74,7 +74,7 @@ bool ParserFilesystemStream::IncludeFile(const std::string& filename)
     if (m_files.empty())
         return false;
     
-    auto newFilePath = fs::path(m_files.top().m_file_path);
+    auto newFilePath = fs::path(*m_files.top().m_file_path);
     newFilePath.remove_filename().concat(filename);
     newFilePath = absolute(newFilePath);
 
diff --git a/src/Parser/Parsing/Impl/ParserFilesystemStream.h b/src/Parser/Parsing/Impl/ParserFilesystemStream.h
index bdca77e5..62870896 100644
--- a/src/Parser/Parsing/Impl/ParserFilesystemStream.h
+++ b/src/Parser/Parsing/Impl/ParserFilesystemStream.h
@@ -10,7 +10,7 @@ class ParserFilesystemStream final : public IParserLineStream
     class FileInfo
     {
     public:
-        std::string m_file_path;
+        std::shared_ptr<std::string> m_file_path;
         std::ifstream m_stream;
         int m_line_number;
 
@@ -19,7 +19,7 @@ class ParserFilesystemStream final : public IParserLineStream
     std::stack<FileInfo> m_files;
 
 public:
-    explicit ParserFilesystemStream(std::string path);
+    explicit ParserFilesystemStream(const std::string& path);
 
     ParserLine NextLine() override;
     bool IncludeFile(const std::string& filename) override;
diff --git a/src/Parser/Parsing/Impl/ParserMultiInputStream.cpp b/src/Parser/Parsing/Impl/ParserMultiInputStream.cpp
index 9fea9e55..78e2d5ee 100644
--- a/src/Parser/Parsing/Impl/ParserMultiInputStream.cpp
+++ b/src/Parser/Parsing/Impl/ParserMultiInputStream.cpp
@@ -5,14 +5,14 @@
 ParserMultiInputStream::FileInfo::FileInfo(std::unique_ptr<std::istream> stream, std::string filePath)
     : m_owned_stream(std::move(stream)),
       m_stream(*m_owned_stream),
-      m_file_path(std::move(filePath)),
+      m_file_path(std::make_shared<std::string>(std::move(filePath))),
       m_line_number(1)
 {
 }
 
 ParserMultiInputStream::FileInfo::FileInfo(std::istream& stream, std::string filePath)
     : m_stream(stream),
-      m_file_path(std::move(filePath)),
+      m_file_path(std::make_shared<std::string>(std::move(filePath))),
       m_line_number(1)
 {
 }
@@ -79,7 +79,7 @@ bool ParserMultiInputStream::IncludeFile(const std::string& filename)
     if (!m_include_callback)
         return false;
 
-    auto newFile = m_include_callback(filename, m_files.empty() ? "" : m_files.top().m_file_path);
+    auto newFile = m_include_callback(filename, m_files.empty() ? "" : *m_files.top().m_file_path);
     if (!newFile)
         return false;
 
diff --git a/src/Parser/Parsing/Impl/ParserMultiInputStream.h b/src/Parser/Parsing/Impl/ParserMultiInputStream.h
index 11b041d2..bd6ee7cb 100644
--- a/src/Parser/Parsing/Impl/ParserMultiInputStream.h
+++ b/src/Parser/Parsing/Impl/ParserMultiInputStream.h
@@ -18,7 +18,7 @@ private:
     public:
         std::unique_ptr<std::istream> m_owned_stream;
         std::istream& m_stream;
-        std::string m_file_path;
+        std::shared_ptr<std::string> m_file_path;
         int m_line_number;
 
         FileInfo(std::unique_ptr<std::istream> stream, std::string filePath);
diff --git a/src/Parser/Parsing/Impl/ParserSingleInputStream.cpp b/src/Parser/Parsing/Impl/ParserSingleInputStream.cpp
index efb965a1..2641a29e 100644
--- a/src/Parser/Parsing/Impl/ParserSingleInputStream.cpp
+++ b/src/Parser/Parsing/Impl/ParserSingleInputStream.cpp
@@ -4,7 +4,7 @@
 
 ParserSingleInputStream::ParserSingleInputStream(std::istream& stream, std::string fileName)
     : m_stream(stream),
-      m_file_name(std::move(fileName)),
+      m_file_name(std::make_shared<std::string>(std::move(fileName))),
       m_line_number(1)
 {
 }
diff --git a/src/Parser/Parsing/Impl/ParserSingleInputStream.h b/src/Parser/Parsing/Impl/ParserSingleInputStream.h
index 4af10424..4a60adbc 100644
--- a/src/Parser/Parsing/Impl/ParserSingleInputStream.h
+++ b/src/Parser/Parsing/Impl/ParserSingleInputStream.h
@@ -1,13 +1,14 @@
 #pragma once
 
 #include <istream>
+#include <memory>
 
 #include "Parsing/IParserLineStream.h"
 
 class ParserSingleInputStream final : public IParserLineStream
 {
     std::istream& m_stream;
-    std::string m_file_name;
+    std::shared_ptr<std::string> m_file_name;
     int m_line_number;
 
 public:
diff --git a/test/ParserTestUtils/Parsing/Mock/MockParserLineStream.cpp b/test/ParserTestUtils/Parsing/Mock/MockParserLineStream.cpp
index 12d03a11..5bae82b4 100644
--- a/test/ParserTestUtils/Parsing/Mock/MockParserLineStream.cpp
+++ b/test/ParserTestUtils/Parsing/Mock/MockParserLineStream.cpp
@@ -2,8 +2,6 @@
 
 #include <algorithm>
 
-const std::string MockParserLineStream::MOCK_FILENAME = "Mockfile";
-
 MockParserLineStream::MockParserLineStream(const std::vector<std::string>& lines)
 {
     AddIncludeLines(MOCK_FILENAME, lines);
@@ -11,7 +9,7 @@ MockParserLineStream::MockParserLineStream(const std::vector<std::string>& lines
 }
 
 MockParserLineStream::IncludePos::IncludePos(std::string filename, const std::vector<std::string>& lines)
-    : m_filename(std::move(filename)),
+    : m_filename(std::make_shared<std::string>(std::move(filename))),
       m_lines(lines),
       m_pos(0)
 {
diff --git a/test/ParserTestUtils/Parsing/Mock/MockParserLineStream.h b/test/ParserTestUtils/Parsing/Mock/MockParserLineStream.h
index 23ac1997..31e10b5b 100644
--- a/test/ParserTestUtils/Parsing/Mock/MockParserLineStream.h
+++ b/test/ParserTestUtils/Parsing/Mock/MockParserLineStream.h
@@ -8,13 +8,13 @@
 class MockParserLineStream final : public IParserLineStream
 {
 public:
-    static const std::string MOCK_FILENAME;
+    static constexpr const char* MOCK_FILENAME = "MockFile";
 
 private:
     class IncludePos
     {
     public:
-        std::string m_filename;
+        std::shared_ptr<std::string> m_filename;
         const std::vector<std::string>& m_lines;
         unsigned m_pos;
 
diff --git a/test/ZoneCodeGeneratorLibTests/Parsing/Impl/IncludingStreamProxyTests.cpp b/test/ZoneCodeGeneratorLibTests/Parsing/Impl/IncludingStreamProxyTests.cpp
index b225b33c..b726f0e2 100644
--- a/test/ZoneCodeGeneratorLibTests/Parsing/Impl/IncludingStreamProxyTests.cpp
+++ b/test/ZoneCodeGeneratorLibTests/Parsing/Impl/IncludingStreamProxyTests.cpp
@@ -27,21 +27,21 @@ namespace test::parsing::impl::including_stream_proxy
         {
             auto line = proxy.NextLine();
             REQUIRE(line.m_line_number == 1);
-            REQUIRE(line.m_filename.get() == MockParserLineStream::MOCK_FILENAME);
+            REQUIRE(*line.m_filename == MockParserLineStream::MOCK_FILENAME);
             REQUIRE(line.m_line == "Hello world");
         }
 
         {
             auto line = proxy.NextLine();
             REQUIRE(line.m_line_number == 1);
-            REQUIRE(line.m_filename.get() == "ASDF.txt");
+            REQUIRE(*line.m_filename == "ASDF.txt");
             REQUIRE(line.m_line == "Hello galaxy");
         }
 
         {
             auto line = proxy.NextLine();
             REQUIRE(line.m_line_number == 3);
-            REQUIRE(line.m_filename.get() == MockParserLineStream::MOCK_FILENAME);
+            REQUIRE(*line.m_filename == MockParserLineStream::MOCK_FILENAME);
             REQUIRE(line.m_line == "and bye");
         }
 
@@ -70,21 +70,21 @@ namespace test::parsing::impl::including_stream_proxy
         {
             auto line = proxy.NextLine();
             REQUIRE(line.m_line_number == 1);
-            REQUIRE(line.m_filename.get() == MockParserLineStream::MOCK_FILENAME);
+            REQUIRE(*line.m_filename == MockParserLineStream::MOCK_FILENAME);
             REQUIRE(line.m_line == "Hello world");
         }
 
         {
             auto line = proxy.NextLine();
             REQUIRE(line.m_line_number == 1);
-            REQUIRE(line.m_filename.get() == "ASDF.txt");
+            REQUIRE(*line.m_filename == "ASDF.txt");
             REQUIRE(line.m_line == "Hello galaxy");
         }
 
         {
             auto line = proxy.NextLine();
             REQUIRE(line.m_line_number == 3);
-            REQUIRE(line.m_filename.get() == MockParserLineStream::MOCK_FILENAME);
+            REQUIRE(*line.m_filename == MockParserLineStream::MOCK_FILENAME);
             REQUIRE(line.m_line == "and bye");
         }
 
@@ -113,21 +113,21 @@ namespace test::parsing::impl::including_stream_proxy
         {
             auto line = proxy.NextLine();
             REQUIRE(line.m_line_number == 1);
-            REQUIRE(line.m_filename.get() == MockParserLineStream::MOCK_FILENAME);
+            REQUIRE(*line.m_filename == MockParserLineStream::MOCK_FILENAME);
             REQUIRE(line.m_line == "Hello world");
         }
 
         {
             auto line = proxy.NextLine();
             REQUIRE(line.m_line_number == 1);
-            REQUIRE(line.m_filename.get() == "ASDF.txt");
+            REQUIRE(*line.m_filename == "ASDF.txt");
             REQUIRE(line.m_line == "Hello galaxy");
         }
 
         {
             auto line = proxy.NextLine();
             REQUIRE(line.m_line_number == 3);
-            REQUIRE(line.m_filename.get() == MockParserLineStream::MOCK_FILENAME);
+            REQUIRE(*line.m_filename == MockParserLineStream::MOCK_FILENAME);
             REQUIRE(line.m_line == "and bye");
         }
 
@@ -158,21 +158,21 @@ namespace test::parsing::impl::including_stream_proxy
         {
             auto line = proxy.NextLine();
             REQUIRE(line.m_line_number == 1);
-            REQUIRE(line.m_filename.get() == MockParserLineStream::MOCK_FILENAME);
+            REQUIRE(*line.m_filename == MockParserLineStream::MOCK_FILENAME);
             REQUIRE(line.m_line == "Hello world");
         }
 
         {
             auto line = proxy.NextLine();
             REQUIRE(line.m_line_number == 2);
-            REQUIRE(line.m_filename.get() == "ASDF.txt");
+            REQUIRE(*line.m_filename == "ASDF.txt");
             REQUIRE(line.m_line == "Hello galaxy");
         }
 
         {
             auto line = proxy.NextLine();
             REQUIRE(line.m_line_number == 4);
-            REQUIRE(line.m_filename.get() == MockParserLineStream::MOCK_FILENAME);
+            REQUIRE(*line.m_filename == MockParserLineStream::MOCK_FILENAME);
             REQUIRE(line.m_line == "and bye");
         }