add from_chars(s, fmt::overflow_checked_<T> *) for generic code

re biojppm/rapidyaml#442

changelog/current.md

@@ -0,0 +1,3 @@
+
+- Add `bool from_chars(csubstr s, fmt::overflow_checked_<T> *wrapper)`. There was already is a function receiving `&wrapper`, but `*wrapper` was missing for use with generic code.
+

src/c4/format.hpp

@@ -323,7 +323,7 @@ to_chars(substr buf, fmt::integral_padded_<T> fmt)
     return utoa(buf, fmt.val, fmt.radix, fmt.num_digits);
 }
 
-/** read an format an integer unsigned type
+/** read an integer type, detecting overflow (returns false on overflow)
  * @ingroup doc_from_chars */
 template<class T>
 C4_ALWAYS_INLINE bool from_chars(csubstr s, fmt::overflow_checked_<T> wrapper)
@@ -332,6 +332,15 @@ C4_ALWAYS_INLINE bool from_chars(csubstr s, fmt::overflow_checked_<T> wrapper)
         return atox(s, wrapper.val);
     return false;
 }
+/** read an integer type, detecting overflow (returns false on overflow)
+ * @ingroup doc_from_chars */
+template<class T>
+C4_ALWAYS_INLINE bool from_chars(csubstr s, fmt::overflow_checked_<T> *wrapper)
+{
+    if(C4_LIKELY(!overflows<T>(s)))
+        return atox(s, wrapper->val);
+    return false;
+}
 
 
 //-----------------------------------------------------------------------------