[ranges] Change "using Parent" declarations to use "maybe-const" after LWG3448

Author: burblebee

source/ranges.tex

@@ -3754,7 +3754,7 @@
   class transform_view<V, F>::@\exposid{iterator}@ {
   private:
     using @\exposid{Parent}@ =                              // \expos
-      conditional_t<Const, const transform_view, transform_view>;
+      @\exposid{maybe-const}@<Const, transform_view>;
     using @\exposid{Base}@   =                              // \expos
       @\exposid{maybe-const}@<Const, V>;
     iterator_t<@\exposid{Base}@> @\exposid{current_}@ =                 // \expos
@@ -4160,7 +4160,7 @@
   class transform_view<V, F>::@\exposid{sentinel}@ {
   private:
     using @\exposid{Parent}@ =                                      // \expos
-      conditional_t<Const, const transform_view, transform_view>;
+      @\exposid{maybe-const}@<Const, transform_view>;
     using @\exposid{Base}@ = @\exposid{maybe-const}@<Const, V>;                 // \expos
     sentinel_t<@\exposid{Base}@> @\exposid{end_}@ = sentinel_t<@\exposid{Base}@>();         // \expos
   public:
@@ -5057,7 +5057,7 @@
   struct join_view<V>::@\exposid{iterator}@ {
   private:
     using @\exposid{Parent}@ =                                              // \expos
-      conditional_t<Const, const join_view, join_view>;
+      @\exposid{maybe-const}@<Const, join_view>;
     using @\exposid{Base}@   = @\exposid{maybe-const}@<Const, V>;                       // \expos
 
     static constexpr bool @\exposid{ref-is-glvalue}@ =                      // \expos
@@ -5369,7 +5369,7 @@
   struct join_view<V>::@\exposid{sentinel}@ {
   private:
     using @\exposid{Parent}@ =                                      // \expos
-      conditional_t<Const, const join_view, join_view>;
+      @\exposid{maybe-const}@<Const, join_view>;
     using @\exposid{Base}@   = @\exposid{maybe-const}@<Const, V>;               // \expos
     sentinel_t<@\exposid{Base}@> @\exposid{end_}@ = sentinel_t<@\exposid{Base}@>();         // \expos
   public:
@@ -5568,7 +5568,7 @@
   struct split_view<V, Pattern>::@\exposid{outer-iterator}@ {
   private:
     using @\exposid{Parent}@ =                          // \expos
-      conditional_t<Const, const split_view, split_view>;
+      @\exposid{maybe-const}@<Const, split_view>;
     using @\exposid{Base}@   =                          // \expos
       @\exposid{maybe-const}@<Const, V>;
     @\exposid{Parent}@* @\exposid{parent_}@ = nullptr;              // \expos