Added error handling

include/util/error.hpp

@@ -0,0 +1,76 @@
+#pragma once
+
+#include <stdexcept>
+#include <optional>
+
+namespace fsh::util {
+    // Generates msg only once what has been called
+    // Usefull for errors meant to be silently discarded frequently
+    class LazyError : public std::exception {
+
+      public:
+        LazyError() {}
+        LazyError(const std::string& msg_) : msg_(msg_) {}
+        LazyError(const char* msg_) : msg_(msg_) {}
+
+        const char* what() const noexcept override;
+
+      protected:
+        mutable std::optional<std::string> msg_;
+
+        virtual std::string build_msg() const noexcept;
+    };
+
+    class CmdNotFoundError : public LazyError {
+      public:
+        CmdNotFoundError(std::string cmd_) : cmd_(cmd_) {}
+
+      protected:
+        std::string build_msg() const noexcept override;
+
+      private:
+        std::string cmd_;
+    };
+
+    class CmdError : public LazyError {
+      public:
+        CmdError(const std::string& msg_) : LazyError(msg_) {}
+        CmdError(const char* msg_) : LazyError(msg_) {}
+    };
+
+    class RuntimeError : public std::exception {
+      public:
+        const char* msg_;
+
+        RuntimeError() = delete;
+        RuntimeError(const char* msg_) : msg_(msg_) {}
+
+        const char* what() const noexcept override;
+    };
+
+    class FileDeleteError : public RuntimeError {
+      public:
+        FileDeleteError() : RuntimeError("Error deleting file") {}
+    };
+
+    class FileExistsError : public RuntimeError {
+      public:
+        FileExistsError() : RuntimeError("File already exists") {}
+    };
+
+    class FileOpenError : public RuntimeError {
+      public:
+        FileOpenError() : RuntimeError("Failed to open file") {}
+    };
+
+    class DoubleInputError : public RuntimeError {
+      public:
+        DoubleInputError() : RuntimeError("Tried to set input twice") {}
+    };
+
+    class LexerError : public LazyError {
+      public:
+        LexerError(const std::string& msg_) : LazyError(msg_) {}
+        LexerError(const char* msg_) : LazyError(msg_) {}
+    };
+}