Everywhere: Add Error class for generic error reporting

The Lexer can now also report errors.

src/ast.cpp

@@ -10,13 +10,6 @@
 
 namespace blaze {
 
-Error::Error(const std::string& error)
-	: m_error(error)
-{
-}
-
-// -----------------------------------------
-
 List::~List()
 {
 	for (auto node : m_nodes) {

src/ast.h

@@ -23,7 +23,6 @@ public:
 	template<typename T>
 	bool fastIs() const = delete;
 
-	virtual bool isError() const { return false; }
 	virtual bool isVector() const { return false; }
 	virtual bool isHashMap() const { return false; }
 	virtual bool isList() const { return false; }
@@ -35,21 +34,6 @@ public:
 
 // -----------------------------------------
 
-class Error final : public ASTNode {
-public:
-	Error(const std::string& error);
-	virtual ~Error() = default;
-
-	virtual bool isError() const override { return true; }
-
-	const std::string& error() const { return m_error; }
-
-private:
-	std::string m_error;
-};
-
-// -----------------------------------------
-
 // []
 class Vector final : public ASTNode {
 public:
@@ -159,9 +143,6 @@ private:
 // -----------------------------------------
 
 // clang-format off
-template<>
-inline bool ASTNode::fastIs<Error>() const { return isError(); }
-
 template<>
 inline bool ASTNode::fastIs<Vector>() const { return isVector(); }
 

src/error.h

@@ -0,0 +1,45 @@
+/*
+ * Copyright (C) 2023 Riyyi
+ *
+ * SPDX-License-Identifier: MIT
+ */
+
+#pragma once
+
+#include <vector>
+
+#include "ruc/singleton.h"
+
+#include "lexer.h"
+
+namespace blaze {
+
+class Error final : public ruc::Singleton<Error> {
+public:
+	Error(s) {}
+	virtual ~Error() = default;
+
+	void clearErrors()
+	{
+		m_token_errors.clear();
+		m_other_errors.clear();
+	}
+	void addError(Token error) { m_token_errors.push_back(error); }
+	void addError(const std::string& error) { m_other_errors.push_back(error); }
+
+	bool hasTokenError() { return m_token_errors.size() > 0; }
+	bool hasOtherError() { return m_other_errors.size() > 0; }
+	bool hasAnyError() { return hasTokenError() || hasOtherError(); }
+
+	void setInput(std::string_view input) { m_input = input; }
+
+	Token tokenError() const { return m_token_errors[0]; }
+	const std::string& otherError() const { return m_other_errors[0]; }
+
+private:
+	std::string_view m_input;
+	std::vector<Token> m_token_errors;
+	std::vector<std::string> m_other_errors;
+};
+
+} // namespace blaze

src/lexer.cpp

@@ -11,6 +11,7 @@
 #include "ruc/format/print.h"
 #include "ruc/genericlexer.h"
 
+#include "error.h"
 #include "lexer.h"
 
 namespace blaze {
@@ -28,7 +29,7 @@ Lexer::~Lexer()
 
 void Lexer::tokenize()
 {
-	if (m_tokens.size() != 0) {
+	if (Error::the().hasAnyError() || m_tokens.size() > 0) {
 		return;
 	}
 
@@ -152,8 +153,9 @@ bool Lexer::consumeString()
 	if (character == '"') {
 		text += character;
 	}
-
-	print("lex text '{}'\n", text);
+	else {
+		Error::the().addError({ Token::Type::Error, m_line, column, "expected '\"', got EOF" });
+	}
 
 	m_tokens.push_back({ Token::Type::String, m_line, column, text });
 

src/lexer.h

@@ -34,6 +34,7 @@ struct Token {
 		String,       // "foobar"
 		Comment,      // ;
 		Value,        // symbols, numbers, "true", "false", and "nil"
+		Error,
 	};
 
 	Type type { Type::None };

src/printer.cpp

@@ -4,8 +4,10 @@
  * SPDX-License-Identifier: MIT
  */
 
+#include "lexer.h"
 #include "ruc/format/print.h"
 
+#include "error.h"
 #include "printer.h"
 #include "types.h"
 
@@ -25,6 +27,11 @@ Printer::~Printer()
 
 void Printer::dump()
 {
+	if (Error::the().hasAnyError()) {
+		dumpError();
+		return;
+	}
+
 	if (m_node == nullptr) {
 		return;
 	}
@@ -41,11 +48,7 @@ void Printer::dumpImpl(ASTNode* node)
 		}
 	};
 
-
-	if (is<Error>(node)) {
-		print("*** blaze error ***  {}", static_cast<Error*>(node)->error());
-	}
-	else if (is<List>(node)) {
+	if (is<List>(node)) {
 		printSpacing();
 		print("(");
 		m_firstNode = false;
@@ -71,4 +74,18 @@ void Printer::dumpImpl(ASTNode* node)
 	}
 }
 
+void Printer::dumpError()
+{
+	print("Error: ");
+	if (Error::the().hasTokenError()) {
+		Token error = Error::the().tokenError();
+		print("{}", error.symbol);
+	}
+	else if (Error::the().hasOtherError()) {
+		std::string error = Error::the().otherError();
+		print("{}", error);
+	}
+	print("\n");
+}
+
 } // namespace blaze

src/printer.h

@@ -20,6 +20,7 @@ public:
 
 private:
 	void dumpImpl(ASTNode* node);
+	void dumpError();
 
 	bool m_firstNode { true };
 	bool m_previousNodeIsList { false };

src/reader.cpp

@@ -9,6 +9,7 @@
 #include <cstdlib> // std::strtoll
 #include <utility> // std::move
 
+#include "error.h"
 #include "ruc/format/color.h"
 #include "ruc/meta/assert.h"
 
@@ -31,7 +32,7 @@ Reader::~Reader()
 
 void Reader::read()
 {
-	if (m_node) {
+	if (Error::the().hasAnyError() || m_node) {
 		return;
 	}
 
@@ -40,26 +41,26 @@ void Reader::read()
 	// Error checking
 
 	if (m_invalid_syntax) {
-		m_node = new Error("Invalid read syntax: '" + std::string(1, m_error_character) + "'");
+		Error::the().addError("invalid read syntax: '" + std::string(1, m_error_character) + "'");
 		return;
 	}
 
 	if (m_is_unbalanced) {
-		m_node = new Error("Expected '" + std::string(1, m_error_character) + "', got EOF");
+		Error::the().addError("expected '" + std::string(1, m_error_character) + "', got EOF");
 		return;
 	}
 
 	if (!isEOF()) {
 		Token::Type type = peek().type;
 		switch (type) {
-		case Token::Type::ParenOpen: // (
+		case Token::Type::ParenOpen:  // (
 		case Token::Type::ParenClose: // )
 		case Token::Type::String:
 		case Token::Type::Value:
-			m_node = new Error("More than one sexp in input");
+			Error::the().addError("more than one sexp in input");
 			break;
 		default:
-			m_node = new Error("Unknown error");
+			Error::the().addError("unknown error");
 			break;
 		};
 	}
@@ -110,39 +111,12 @@ ASTNode* Reader::readList()
 	return list;
 }
 
-static bool isValidString(const std::string& str)
-{
-	if (str.size() < 2 || str.front() != '"' || str.back() != '"') {
-		return false;
-	}
-	if (str.size() == 2) {
-		return true;
-	}
-
-	bool escaped = false;
-	for (auto it = str.begin() + 1; it != str.end() - 1; ++it) {
-		if (*it == '\\' && !escaped) {
-			escaped = true;
-			continue;
-		}
-
-		// The last character needs to be an escaped '\' or not a '\'
-		if (it == str.end() - 2 && (escaped || *it != '\\')) {
-			return true;
-		}
-
-		escaped = false;
-	}
-
-	return false;
-}
-
 ASTNode* Reader::readString()
 {
 	std::string symbol = consume().symbol;
 
 	// Unbalanced string
-	if (!isValidString(symbol)) {
+	if (symbol.size() < 2 || symbol.front() != '"' || symbol.back() != '"') {
 		m_error_character = '"';
 		m_is_unbalanced = true;
 	}

src/step1_read_print.cpp

@@ -4,6 +4,7 @@
 #include <string>   // std::getline
 #include <string_view>
 
+#include "error.h"
 #include "ruc/format/color.h"
 
 #include "ast.h"
@@ -14,9 +15,9 @@
 #define PRETTY_PRINT 0
 
 #if 1
-auto read(std::string_view data) -> blaze::ASTNode*
+auto read(std::string_view input) -> blaze::ASTNode*
 {
-	blaze::Lexer lexer(data);
+	blaze::Lexer lexer(input);
 	lexer.tokenize();
 	// lexer.dump();
 	blaze::Reader reader(std::move(lexer.tokens()));
@@ -37,9 +38,12 @@ auto print(blaze::ASTNode* node) -> void
 	printer.dump();
 }
 
-auto rep(std::string_view data) -> void
+auto rep(std::string_view input) -> void
 {
-	print(eval(read(data)));
+	blaze::Error::the().clearErrors();
+	blaze::Error::the().setInput(input);
+
+	print(eval(read(input)));
 }
 
 static auto cleanup(int signal) -> void