region: constructors should be constexpr

region.cpp

@@ -18,33 +18,7 @@
 using cruft::region;
 
 
-//-----------------------------------------------------------------------------
-template <size_t S, typename T>
-cruft::region<S,T>::region (point_t  _p,
-                           extent_t _e):
-    p (_p),
-    e (_e)
-{
-    CHECK_SANITY (*this);
-}
-
-
-//-----------------------------------------------------------------------------
-template <size_t S, typename T>
-cruft::region<S,T>::region (point_t _a,
-                           point_t _b):
-    region (_a, extent_t { _b - _a })
-{
-    // This check must allow for zero area (but non-zero dimension) regions.
-    // Some code paths need to support this degenerate case. It's ugly but
-    // simplifies generalisation. eg, vertical linear bezier curves.
-    CHECK (all (_a <= _b));
-
-    CHECK_SANITY (*this);
-}
-
-
-//-----------------------------------------------------------------------------
+///////////////////////////////////////////////////////////////////////////////
 template <size_t S, typename T>
 typename cruft::region<S,T>::extent_t
 cruft::region<S,T>::magnitude (void) const

region.hpp

@@ -37,8 +37,14 @@ namespace cruft {
 
         //---------------------------------------------------------------------
         region () = default;
-        region (point_t, extent_t);
-        region (point_t, point_t);
+        constexpr region (point_t _p, extent_t _e)
+            : p (_p)
+            , e (_e)
+        { ; }
+
+        constexpr region (point_t _a, point_t _b)
+            : region (_a, extent_t (_b - _a))
+        { ; }
 
 
         //---------------------------------------------------------------------