Implement sequence matcher and parser magic

src/ZoneCodeGeneratorLib/Parsing/Matcher/MatcherOptional.h

@@ -0,0 +1,33 @@
+#pragma once
+
+#include <iterator>
+#include <memory>
+
+#include "Parsing/IParserValue.h"
+#include "AbstractMatcher.h"
+
+template <typename TokenType>
+class MatcherOptional final : public AbstractMatcher<TokenType>
+{
+    // TokenType must inherit IParserValue
+    static_assert(std::is_base_of<IParserValue, TokenType>::value);
+
+    std::unique_ptr<AbstractMatcher<TokenType>> m_matcher;
+
+protected:
+    MatcherResult<TokenType> CanMatch(AbstractLexer<TokenType>* lexer, unsigned tokenOffset) override
+    {
+        auto result = m_matcher->Match(lexer, tokenOffset);
+
+        if (result.m_matches)
+            return result;
+
+        return MatcherResult<TokenType>::Match(0);
+    }
+
+public:
+    explicit MatcherOptional(std::unique_ptr<AbstractMatcher<TokenType>> matcher)
+        : m_matcher(std::move(matcher))
+    {
+    }
+};