....

common/adc_traits.h

@@ -46,6 +46,10 @@ template <typename R>
 concept adc_char_view = std::ranges::view<R> && std::same_as<std::ranges::range_value_t<R>, char>;
 
 
+template <typename R>
+concept adc_range_of_view_char_range = std::ranges::range<R> && std::ranges::view<std::ranges::range_value_t<R>> &&
+                                       std::same_as<std::ranges::range_value_t<std::ranges::range_value_t<R>>, char>;
+
 // deduce returned type of callable
 // template <typename T>
 // using adc_retval_t = std::invoke_result_t<std::remove_cvref_t<T>>;

common/adc_utils.h

@@ -441,4 +441,62 @@ public:
     }
 };
 
+
+/*  join range elements using delimiter between its elements  */
+
+// NOTE: C++23 has std::views::join_with adapter but here I use upto C++20!!!
+template <std::ranges::input_range R,
+          std::ranges::input_range RD,
+          std::ranges::output_range<std::ranges::range_value_t<RD>> RO>
+static size_t AdcJoinRange(R& r, const RD& delim, RO& ro)
+    requires std::ranges::range<std::ranges::range_value_t<R>> &&  // input R is range of ranges
+             std::same_as<std::ranges::range_value_t<std::ranges::range_value_t<R>>, std::ranges::range_value_t<RD>>
+{
+    auto N = std::ranges::distance(r.begin(), r.end());
+
+    if (!N) {
+        return 0;
+    }
+
+    size_t i = 0;
+
+    std::ranges::for_each(r, [&](const auto& el) {
+        std::ranges::copy(el, std::back_inserter(ro));
+        if (++i < N) {
+            std::ranges::copy(delim, std::back_inserter(ro));
+        }
+    });
+
+
+    return N;
+}
+
+
+// create a range with views of elements of input range and insert a view of input delimiter between them
+
+template <std::ranges::input_range R, std::ranges::input_range RD, std::ranges::range RO>
+static size_t AdcReturnRangeElementsView(const R& r, const RD& delim, RO& ro)
+    requires std::ranges::range<std::ranges::range_value_t<R>> &&  // input R is range of ranges
+             std::same_as<std::ranges::range_value_t<std::ranges::range_value_t<R>>, std::ranges::range_value_t<RD>> &&
+             std::ranges::view<std::ranges::range_value_t<RO>> &&  // output RO is range of views
+             std::same_as<std::ranges::range_value_t<std::ranges::range_value_t<RO>>, std::ranges::range_value_t<RD>>
+{
+    auto N = std::ranges::distance(r.begin(), r.end());
+
+    if (!N) {
+        return 0;
+    }
+
+    size_t i = 0;
+
+    std::ranges::for_each(r, [&](const auto& el) {
+        std::back_inserter(ro) = {el.begin(), el.end()};
+        if (++i < N) {
+            std::back_inserter(ro) = {delim.begin(), delim.end()};
+        }
+    });
+
+    return N;
+}
+
 }  // namespace adc::utils