Return types

taehyounpark · Feb 16, 2024 · 2d47b94 · 2d47b94
1 parent 3a8e3ba
commit 2d47b94
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Showing 2 changed files with 16 additions and 6 deletions.
diff --git a/include/ana/interface/column.h b/include/ana/interface/column.h
@@ -88,6 +88,11 @@ struct equation_traits<std::function<Ret(Args...)>> {
       column::equation<std::decay_t<Ret>(std::decay_t<Args>...)>;
 };
 
+template <typename Expr> struct equation_traits<expression<Expr>> {
+  using function_type = typename expression<Expr>::function_type;
+  using equation_type = typename equation_traits<function_type>::equation_type;
+};
+
 template <typename F>
 using equation_t = typename equation_traits<F>::equation_type;
 

diff --git a/include/ana/interface/dataflow.h b/include/ana/interface/dataflow.h
@@ -87,13 +87,16 @@ class dataflow {
   template <typename F> auto _equate(F fn);
   template <typename Expr> auto _equate(column::expression<Expr> const &expr);
 
-  template <typename Val> auto define(column::constant<Val> const &cnst);
+  template <typename Val>
+  auto define(column::constant<Val> const &cnst) -> lazy<column::fixed<Val>>;
 
   template <typename Def, typename... Cols>
-  auto define(column::definition<Def> const &defn, Cols const &...cols);
+  auto define(column::definition<Def> const &defn, Cols const &...cols)
+      -> lazy<Def>;
 
   template <typename Expr, typename... Cols>
-  auto define(column::expression<Expr> const &expr, Cols const &...cols);
+  auto define(column::expression<Expr> const &expr, Cols const &...cols)
+      -> lazy<column::equation_t<ana::column::expression<Expr>>>;
 
   template <typename Sel, typename F>
   auto _select(F fn) -> delayed<selection::template custom_applicator_t<F>>;
@@ -286,19 +289,21 @@ auto ana::dataflow::open(ana::dataset::input<DS> &&input)
 }
 
 template <typename Val>
-auto ana::dataflow::define(ana::column::constant<Val> const &cnst) {
+auto ana::dataflow::define(ana::column::constant<Val> const &cnst)
+    -> lazy<column::fixed<Val>> {
   return cnst._assign(*this);
 }
 
 template <typename Def, typename... Cols>
 auto ana::dataflow::define(ana::column::definition<Def> const &defn,
-                           Cols const &...cols) {
+                           Cols const &...cols) -> lazy<Def> {
   return this->_define(defn).template evaluate(cols...);
 }
 
 template <typename Expr, typename... Cols>
 auto ana::dataflow::define(ana::column::expression<Expr> const &expr,
-                           Cols const &...cols) {
+                           Cols const &...cols)
+    -> lazy<column::equation_t<ana::column::expression<Expr>>> {
   return this->_equate(expr).template evaluate(cols...);
 }