Main+Eval: Implement tail call optimization (TCO)

src/step5_tco.cpp

@@ -0,0 +1,136 @@
+/*
+ * Copyright (C) 2023 Riyyi
+ *
+ * SPDX-License-Identifier: MIT
+ */
+
+#include <csignal> // std::signal
+#include <cstdlib> // std::exit
+#include <string>
+#include <string_view>
+
+#include "ruc/argparser.h"
+#include "ruc/format/color.h"
+
+#include "ast.h"
+#include "environment.h"
+#include "error.h"
+#include "eval.h"
+#include "forward.h"
+#include "lexer.h"
+#include "printer.h"
+#include "reader.h"
+#include "readline.h"
+#include "settings.h"
+
+#if 1
+static blaze::EnvironmentPtr s_outer_env = blaze::Environment::create();
+
+static auto cleanup(int signal) -> void;
+static auto installLambdas(blaze::EnvironmentPtr env) -> void;
+static auto rep(std::string_view input, blaze::EnvironmentPtr env) -> std::string;
+static auto read(std::string_view input) -> blaze::ASTNodePtr;
+static auto eval(blaze::ASTNodePtr ast, blaze::EnvironmentPtr env) -> blaze::ASTNodePtr;
+static auto print(blaze::ASTNodePtr exp) -> std::string;
+
+auto main(int argc, char* argv[]) -> int
+{
+	bool dump_lexer = false;
+	bool dump_reader = false;
+	bool pretty_print = false;
+	std::string_view history_path = "~/.mal-history";
+
+	// CLI arguments
+	ruc::ArgParser arg_parser;
+	arg_parser.addOption(dump_lexer, 'l', "dump-lexer", nullptr, nullptr);
+	arg_parser.addOption(dump_reader, 'r', "dump-reader", nullptr, nullptr);
+	arg_parser.addOption(pretty_print, 'c', "color", nullptr, nullptr);
+	arg_parser.addOption(history_path, 'h', "history", nullptr, nullptr, nullptr, ruc::ArgParser::Required::Yes);
+	arg_parser.parse(argc, argv);
+
+	// Set settings
+	blaze::Settings::the().set("dump-lexer", dump_lexer ? "1" : "0");
+	blaze::Settings::the().set("dump-reader", dump_reader ? "1" : "0");
+	blaze::Settings::the().set("pretty-print", pretty_print ? "1" : "0");
+
+	// Signal callbacks
+	std::signal(SIGINT, cleanup);
+	std::signal(SIGTERM, cleanup);
+
+	installFunctions(s_outer_env);
+	installLambdas(s_outer_env);
+
+	blaze::Readline readline(pretty_print, history_path);
+
+	std::string input;
+	while (readline.get(input)) {
+		if (pretty_print) {
+			print("\033[0m");
+		}
+		print("{}\n", rep(input, s_outer_env));
+	}
+
+	if (pretty_print) {
+		print("\033[0m");
+	}
+
+	return 0;
+}
+
+static auto cleanup(int signal) -> void
+{
+	print("\033[0m\n");
+	std::exit(signal);
+}
+
+static std::string_view lambdaTable[] = {
+	"(def! not (fn* (cond) (if cond false true)))",
+};
+
+static auto installLambdas(blaze::EnvironmentPtr env) -> void
+{
+	for (auto function : lambdaTable) {
+		rep(function, env);
+	}
+}
+
+static auto rep(std::string_view input, blaze::EnvironmentPtr env) -> std::string
+{
+	blaze::Error::the().clearErrors();
+	blaze::Error::the().setInput(input);
+
+	return print(eval(read(input), env));
+}
+
+static auto read(std::string_view input) -> blaze::ASTNodePtr
+{
+	blaze::Lexer lexer(input);
+	lexer.tokenize();
+	if (blaze::Settings::the().get("dump-lexer") == "1") {
+		lexer.dump();
+	}
+
+	blaze::Reader reader(std::move(lexer.tokens()));
+	reader.read();
+	if (blaze::Settings::the().get("dump-reader") == "1") {
+		reader.dump();
+	}
+
+	return reader.node();
+}
+
+static auto eval(blaze::ASTNodePtr ast, blaze::EnvironmentPtr env) -> blaze::ASTNodePtr
+{
+	blaze::Eval eval(ast, env);
+	eval.eval();
+
+	return eval.ast();
+}
+
+static auto print(blaze::ASTNodePtr exp) -> std::string
+{
+	blaze::Printer printer;
+
+	return printer.print(exp, true);
+}
+#endif