Util: Add two functions to GenericLexer

- tellRemaining
- consumeSpecific

src/util/genericlexer.cpp

@@ -26,6 +26,11 @@ size_t GenericLexer::tell() const
 	return m_index;
 }
 
+size_t GenericLexer::tellRemaining() const
+{
+	return m_input.length() - m_index;
+}
+
 bool GenericLexer::isEOF() const
 {
 	return m_index >= m_input.length();
@@ -33,7 +38,9 @@ bool GenericLexer::isEOF() const
 
 char GenericLexer::peek(size_t offset) const
 {
-	return m_input[std::max(std::min(m_index + offset, m_input.length()), (size_t)0)];
+	return (m_index + offset >= 0 && m_index + offset < m_input.length())
+	           ? m_input[m_index + offset]
+	           : '\0';
 }
 
 void GenericLexer::ignore(size_t count)
@@ -52,4 +59,14 @@ char GenericLexer::consume()
 	return m_input[m_index++];
 }
 
+bool GenericLexer::consumeSpecific(const char& character)
+{
+	if (peek() != character) {
+		return false;
+	}
+
+	ignore();
+	return true;
+}
+
 } // namespace Util

src/util/genericlexer.h

@@ -21,6 +21,7 @@ public:
 	// Position
 
 	size_t tell() const;
+	size_t tellRemaining() const;
 	bool isEOF() const;
 
 	// Access
@@ -32,6 +33,7 @@ public:
 	void ignore(size_t count = 1);
 	void retreat(size_t count = 1);
 	char consume();
+	bool consumeSpecific(const char& character);
 
 protected:
 	size_t m_index { 0 };