fix multiple different code smells

power_grid_model_c/power_grid_model/include/power_grid_model/component/load_gen.hpp

@@ -64,7 +64,13 @@ class LoadGen final : public std::conditional_t<is_gen, GenericGenerator, Generi
     using InputType = LoadGenInput<sym>;
     using UpdateType = LoadGenUpdate<sym>;
     using BaseClass = std::conditional_t<is_gen, GenericGenerator, GenericLoad>;
-    static constexpr char const* name = sym ? (is_gen ? "sym_gen" : "sym_load") : (is_gen ? "asym_gen" : "asym_load");
+    static constexpr char const* name = [] {
+        if constexpr (sym) {
+            return is_gen ? "sym_gen" : "sym_load";
+        } else {
+            return is_gen ? "asym_gen" : "asym_load";
+        }
+    }();
 
     LoadGen(LoadGenInput<sym> const& load_gen_input, double u) : BaseClass{load_gen_input, u} {
         set_power(load_gen_input.p_specified, load_gen_input.q_specified);

power_grid_model_c/power_grid_model/include/power_grid_model/math_solver/block_matrix.hpp

@@ -16,7 +16,14 @@ namespace power_grid_model::math_model_impl {
 
 template <scalar_value T, bool sym, bool is_tensor, int n_sub_block> struct block_trait {
     static constexpr int n_row = sym ? n_sub_block : n_sub_block * 3;
-    static constexpr int n_col = is_tensor ? (sym ? n_sub_block : n_sub_block * 3) : 1;
+    static constexpr int n_col = [] {
+        if constexpr (is_tensor) {
+            return sym ? n_sub_block : n_sub_block * 3;
+        } else {
+            return 1;
+        }
+    }();
+
     using ArrayType = Eigen::Array<T, n_row, n_col, Eigen::ColMajor>;
 };
 

power_grid_model_c/power_grid_model/include/power_grid_model/math_solver/y_bus.hpp

@@ -205,7 +205,7 @@ struct YBusStructure {
                 }
                 // all entries in the same position are looped, append indptr
                 // need to be offset by fill-in
-                y_bus_entry_indptr.push_back(static_cast<Idx>(it_element - vec_map_element.cbegin()) - fill_in_counter);
+                y_bus_entry_indptr.push_back((it_element - vec_map_element.cbegin()) - fill_in_counter);
                 // iterate linear nnz
                 ++nnz_counter;
                 ++nnz_counter_lu;

power_grid_model_c/power_grid_model/include/power_grid_model/topology.hpp

@@ -92,7 +92,7 @@ class Topology {
         // assign node to math group
         // append node to dfs list
         void discover_vertex(GlobalGraph::vertex_descriptor u, GlobalGraph const& /* unused_value */) {
-            node_coupling_[u].group = static_cast<Idx>(math_group_);
+            node_coupling_[u].group = math_group_;
             dfs_node_.push_back(static_cast<Idx>(u));
         }