refactor(dev): unify compiler error logging

src/utils/Log.cpp

@@ -5,6 +5,48 @@
 #include "utils/Log.h"
 
 #include <ostream>
+#include <string>
+
+namespace {
+
+bool IsCLIError(const std::string_view msg) {
+  return HasErrorPrefix(msg, "cli");
+}
+
+}  // namespace
+
+void LogInfo(const std::string_view msg, std::ostream& os) {
+  os << "[info] " << msg << "\n";
+}
+
+void LogError(const std::string_view msg, std::ostream& os) {
+  os << "[error] " << msg << "\n";
+}
+
+std::string FormatError(const std::string_view stage,
+                        const std::string_view msg) {
+  return "[" + std::string(stage) + "] " + std::string(msg);
+}
+
+std::string FormatErrorAt(const std::string_view stage, const std::size_t line,
+                          const std::size_t column,
+                          const std::string_view msg) {
+  return "[" + std::string(stage) + "] @" + std::to_string(line) + ":" +
+         std::to_string(column) + " - " + std::string(msg);
+}
+
+bool HasErrorPrefix(const std::string_view msg, const std::string_view stage) {
+  const std::string prefix = "[" + std::string(stage) + "]";
+  return msg.rfind(prefix, 0) == 0;
+}
+
+void PrintException(std::ostream& os, const std::exception& ex) {
+  LogError(ex.what(), os);
+  if (IsCLIError(ex.what())) {
+    os << "\n";
+    PrintHelp(os);
+  }
+}
 
 void PrintHelp(std::ostream& os) {
   os << "SysY Compiler (课程实验最小可运行示例)\n"