Tidy up router static handler checks

vinniefalco · vinniefalco · commit 00131e21b2a8 · 2026-01-18T14:28:17.000-08:00
diff --git a/include/boost/http/server/router.hpp b/include/boost/http/server/router.hpp
@@ -488,8 +488,10 @@ class router : public detail::router_base
     {
         static_assert(handler_crvals<H1, HN...>,
             "pass handlers by value or std::move()");
-        static_assert(handler_check<7, H1, HN...>,
+        static_assert(! handler_check<8, H1, HN...>,
             "cannot use exception handlers here");
+        static_assert(handler_check<7, H1, HN...>,
+            "invalid handler signature");
         add_impl(pattern, make_handlers(
             std::forward<H1>(h1), std::forward<HN>(hn)...));
     }
@@ -532,8 +534,10 @@ class router : public detail::router_base
     {
         static_assert(handler_crvals<H1, HN...>,
             "pass handlers by value or std::move()");
-        static_assert(handler_check<7, H1, HN...>,
+        static_assert(! handler_check<8, H1, HN...>,
             "cannot use exception handlers here");
+        static_assert(handler_check<7, H1, HN...>,
+            "invalid handler signature");
         use(std::string_view(),
             std::forward<H1>(h1), std::forward<HN>(hn)...);
     }

Original file line number	Diff line number	Diff line change
`@@ -488,8 +488,10 @@ class router : public detail::router_base`
`488`	`488`	`{`
`489`	`489`	`static_assert(handler_crvals<H1, HN...>,`
`490`	`490`	`"pass handlers by value or std::move()");`
`491`		`- static_assert(handler_check<7, H1, HN...>,`
	`491`	`+ static_assert(! handler_check<8, H1, HN...>,`
`492`	`492`	`"cannot use exception handlers here");`
	`493`	`+ static_assert(handler_check<7, H1, HN...>,`
	`494`	`+ "invalid handler signature");`
`493`	`495`	`add_impl(pattern, make_handlers(`
`494`	`496`	`std::forward<H1>(h1), std::forward<HN>(hn)...));`
`495`	`497`	`}`
`@@ -532,8 +534,10 @@ class router : public detail::router_base`
`532`	`534`	`{`
`533`	`535`	`static_assert(handler_crvals<H1, HN...>,`
`534`	`536`	`"pass handlers by value or std::move()");`
`535`		`- static_assert(handler_check<7, H1, HN...>,`
	`537`	`+ static_assert(! handler_check<8, H1, HN...>,`
`536`	`538`	`"cannot use exception handlers here");`
	`539`	`+ static_assert(handler_check<7, H1, HN...>,`
	`540`	`+ "invalid handler signature");`
`537`	`541`	`use(std::string_view(),`
`538`	`542`	`std::forward<H1>(h1), std::forward<HN>(hn)...);`
`539`	`543`	`}`