1 files changed, 12 insertions, 2 deletions
diff --git a/c/defs.h b/c/defs.h
index 5a6a25a..102dce2 100644
--- a/c/defs.h
+++ b/c/defs.h
@@ -3,16 +3,26 @@
 
 #include <memory>
 #include <optional>
+#include <stdexcept>
 #include <windows.h>
 #include <commctrl.h>
 #include <SWI-Prolog.h>
 
 /* common.cpp */
 TCHAR *TszFromSz(const char *, int);
+struct Win32Error : public std::exception
+{
+	Win32Error(DWORD);
+	~Win32Error(void);
+	virtual const char *what(void) const noexcept override;
+private:
+	DWORD m_dwErr;
+	char *m_szMsg = NULL;
+};
 struct Library
 {
 	Library(const TCHAR *);
-	~Library();
+	~Library(void);
 	FARPROC GetProcAddress(const char *);
 private:
 	HMODULE m_hModule;
@@ -70,7 +80,7 @@ int Plx(const char *, const char *);
 struct Query
 {
 	Query(module_t ctx, predicate_t p, term_t t0);
-	~Query();
+	~Query(void);
 	int Cut();
 	int Close();
 	int NextSolution();