cmList: Add container conversion to string

1 files changed, 38 insertions, 3 deletions

diff --git a/Source/cmList.h b/Source/cmList.h
index eba0400..9ee4a46 100644
--- a/Source/cmList.h
+++ b/Source/cmList.h
@@ -22,6 +22,9 @@
 
 #include "cmValue.h"
 
+template <typename T>
+class BT;
+
 /**
  * CMake lists management
  * A CMake list is a string where list elements are separated by the ';'
@@ -936,7 +939,10 @@ public:
                     std::vector<std::string> const& args,
                     std::unique_ptr<TransformSelector> = {});
 
-  std::string join(cm::string_view glue) const;
+  std::string join(cm::string_view glue) const
+  {
+    return cmList::Join(this->Values, glue);
+  }
 
   void swap(cmList& other) noexcept { this->Values.swap(other.Values); }
 
@@ -1092,8 +1098,8 @@ public:
     return cmList::append(list,
                           cm::string_view{ std::accumulate(
                             std::next(first), last, *first,
-                            [](std::string a, const std::string& b) {
-                              return std::move(a) +
+                            [](const std::string& a, const std::string& b) {
+                              return a +
                                 std::string(cmList::element_separator) + b;
                             }) });
   }
@@ -1116,6 +1122,13 @@ public:
                              }) });
   }
 
+  template <typename Range,
+            cm::enable_if_t<cm::is_range<Range>::value, int> = 0>
+  static std::string to_string(Range const& r)
+  {
+    return cmList::Join(r, cmList::element_separator);
+  }
+
   // Non-members
   // ===========
   friend inline bool operator==(const cmList& lhs, const cmList& rhs) noexcept
@@ -1185,6 +1198,28 @@ private:
     return container.begin() + delta;
   }
 
+  static std::string const& ToString(std::string const& s) { return s; }
+  static std::string ToString(cm::string_view s) { return std::string{ s }; }
+  static std::string const& ToString(BT<std::string> const&);
+
+  template <typename Range>
+  static std::string Join(Range const& r, cm::string_view glue)
+  {
+    if (cm::size(r) == 0) {
+      return std::string{};
+    }
+
+    const auto sep = std::string{ glue };
+
+    return std::accumulate(
+      std::next(std::begin(r)), std::end(r), cmList::ToString(*std::begin(r)),
+      [&sep](std::string const& a,
+             typename std::iterator_traits<decltype(std::begin(
+               r))>::value_type const& b) -> std::string {
+        return a + sep + cmList::ToString(b);
+      });
+  }
+
   container_type Values;
 };