Add wstring_owner, replacing std::wstring.

std::basic_string is nice, but it is not very ergonomic if everything
you really need is to automatically free C strings at end of scope.

I suppose I could have used std::unique_ptr for this, but I suspect
the ergonomics would be worse.

1 files changed, 5 insertions, 4 deletions

diff --git a/c/pl.cpp b/c/pl.cpp
index 665fe3a..1255609 100644
--- a/c/pl.cpp
+++ b/c/pl.cpp
@@ -90,10 +90,11 @@ int Query::NextSolution()
 }
 
 /* Convert Prolog term to wide characters. */
-int PlString(const term_t t, std::wstring* const pWs, const int iFlags)
+wstring_owner PlString(const term_t t, const int iFlags)
 {
 	char* sz;
-	int r = PL_get_chars(t, &sz, iFlags);
-	if (r) *pWs = WsFromSz(sz);
-	return r;
+	if (PL_get_chars(t, &sz, iFlags))
+		return {WsoFromSz(sz)};
+	else
+		return {};
 }