view: clarify helper func of end()

PaulXiCao · PaulXiCao · commit 68976baa38d4 · 2024-11-17T14:49:46.000+01:00
diff --git a/libcxx/include/__ranges/cartesian_product_view.h b/libcxx/include/__ranges/cartesian_product_view.h
@@ -143,11 +143,11 @@ class cartesian_product_view : public view_interface<cartesian_product_view<Firs
     return it;
   }
 
-  template <auto N = 0>
+  template <auto N = 1>
   constexpr bool end_is_empty() const {
-    if constexpr (N == sizeof...(Vs))
+    if constexpr (N == 1 + sizeof...(Vs))
       return false;
-    if (const auto& v = std::get<N + 1>(bases_); ranges::empty(v))
+    if (const auto& v = std::get<N>(bases_); ranges::empty(v))
       return true;
     return end_is_empty<N + 1>();
   }

Original file line number	Diff line number	Diff line change
`@@ -143,11 +143,11 @@ class cartesian_product_view : public view_interface<cartesian_product_view<Firs`
`143`	`143`	`return it;`
`144`	`144`	`}`
`145`	`145`
`146`		`- template <auto N = 0>`
	`146`	`+ template <auto N = 1>`
`147`	`147`	`constexpr bool end_is_empty() const {`
`148`		`- if constexpr (N == sizeof...(Vs))`
	`148`	`+ if constexpr (N == 1 + sizeof...(Vs))`
`149`	`149`	`return false;`
`150`		`- if (const auto& v = std::get<N + 1>(bases_); ranges::empty(v))`
	`150`	`+ if (const auto& v = std::get<N>(bases_); ranges::empty(v))`
`151`	`151`	`return true;`
`152`	`152`	`return end_is_empty<N + 1>();`
`153`	`153`	`}`