[WIP][FEA] Support ANSI SQL operators in Transform

cpp/CMakeLists.txt

@@ -337,6 +337,7 @@ add_library(
   src/aggregation/result_cache.cpp
   src/ast/expression_parser.cpp
   src/ast/expressions.cpp
+  src/ast/jit_expressions.cpp
   src/ast/operators.cpp
   src/binaryop/binaryop.cpp
   src/binaryop/compiled/ATan2.cu

cpp/include/cudf/ast/detail/operator_functor.cuh

@@ -778,12 +778,5 @@ struct operator_functor<ast_operator::NULL_LOGICAL_OR, true> {
   }
 };
 
-constexpr bool flatten_predicate(possibly_null_value_t<bool, false> value) { return value; }
-
-constexpr bool flatten_predicate(possibly_null_value_t<bool, true> value)
-{
-  return value.has_value() && *value;
-}
-
 }  // namespace ast::detail
 }  // namespace CUDF_EXPORT cudf

cpp/include/cudf/ast/expressions.hpp

@@ -59,7 +59,7 @@ class expression_transformer;
  * This class is a part of a "visitor" pattern with the `expression_parser` class.
  * Expressions inheriting from this class can accept parsers as visitors.
  */
-struct expression {
+struct [[nodiscard]] expression {
   /**
    * @brief Accepts a visitor class.
    *
@@ -514,17 +514,17 @@ class operation : public expression {
 
 namespace detail {
 
-/// @brief An expression that represents a filter predicate.
+/// @brief An expression that represents a predicate.
 ///
 /// This is an internal expression used in filter operations. It is not intended to be used by
 /// external code and is not a part of the public API.
-class filter_predicate : public expression {
+class predicate : public expression {
  public:
   /**
    * @brief Construct a new filter predicate object
    * @param source The source expression from which the predicate value is taken
    */
-  filter_predicate(expression const& source) : source_{source} {}
+  predicate(expression const& source) : source_{source} {}
 
   /**
    * @copydoc expression::accept