Simplify a few loops using std::ranges::reverse_view

Automatically detected using clang-tidy with modernize-loop-convert check.

src/DynamicModel.cc

@@ -23,6 +23,7 @@
 #include <cstdlib>
 #include <iostream>
 #include <numeric>
+#include <ranges>
 #include <regex>
 #include <sstream>
 #include <string_view>
@@ -3485,18 +3486,18 @@ void
 DynamicModel::detrendEquations()
 {
   // We go backwards in the list of trend_vars, to deal correctly with I(2) processes
-  for (auto it = nonstationary_symbols_map.crbegin(); it != nonstationary_symbols_map.crend(); ++it)
+  for (const auto& it : std::ranges::reverse_view(nonstationary_symbols_map))
     {
       for (auto& equation : equations)
         {
           equation = dynamic_cast<BinaryOpNode*>(
-              equation->detrend(it->first, it->second.first, it->second.second));
+              equation->detrend(it.first, it.second.first, it.second.second));
           assert(equation);
         }
       for (auto& equation : static_only_equations)
         {
           equation = dynamic_cast<BinaryOpNode*>(
-              equation->detrend(it->first, it->second.first, it->second.second));
+              equation->detrend(it.first, it.second.first, it.second.second));
           assert(equation);
         }
     }

src/ModelEquationBlock.cc

@@ -19,6 +19,7 @@
 
 #include <algorithm>
 #include <cassert>
+#include <ranges>
 #include <sstream>
 
 #include "ModelEquationBlock.hh"
@@ -385,10 +386,10 @@ void
 Epilogue::detrend(const map<int, expr_t>& trend_symbols_map,
                   const nonstationary_symbols_map_t& nonstationary_symbols_map)
 {
-  for (auto it = nonstationary_symbols_map.crbegin(); it != nonstationary_symbols_map.crend(); ++it)
+  for (const auto& it : ranges::reverse_view(nonstationary_symbols_map))
     for (auto& [symb_id, expr] : dynamic_def_table)
       {
-        expr = expr->detrend(it->first, it->second.first, it->second.second);
+        expr = expr->detrend(it.first, it.second.first, it.second.second);
         assert(expr);
       }
 

src/VariableDependencyGraph.cc

@@ -29,6 +29,7 @@
 #include <boost/graph/strong_components.hpp>
 #include <boost/graph/topological_sort.hpp>
 #pragma GCC diagnostic pop
+#include <ranges>
 
 using namespace boost;
 
@@ -325,8 +326,8 @@ VariableDependencyGraph::reorderRecursiveVariables(const set<int>& feedback_vert
   auto v_index = get(vertex_index, G);
 
   // Suppress feedback vertices, in decreasing order
-  for (auto it = feedback_vertices.rbegin(); it != feedback_vertices.rend(); ++it)
-    G.suppress(*it);
+  for (int feedback_vertex : ranges::reverse_view(feedback_vertices))
+    G.suppress(feedback_vertex);
 
   bool something_has_been_done = true;
   while (something_has_been_done)