Method Evaluate

eval/eval/function_step.cc:435–472

        resolver_(std::forward<Resolver>(resolver)) {}

  absl::Status Evaluate(ExecutionFrameBase& frame, cel::Value& result,
                        AttributeTrail& trail) const override {
    absl::InlinedVector<Value, 2> args;
    absl::InlinedVector<AttributeTrail, 2> arg_trails;

    args.resize(arg_steps_.size());
    arg_trails.resize(arg_steps_.size());

    for (size_t i = 0; i < arg_steps_.size(); i++) {
      CEL_RETURN_IF_ERROR(
          arg_steps_[i]->Evaluate(frame, args[i], arg_trails[i]));
    }

    if (frame.unknown_processing_enabled()) {
      for (size_t i = 0; i < arg_trails.size(); i++) {
        if (frame.attribute_utility().CheckForUnknown(arg_trails[i],
                                                      /*use_partial=*/true)) {
          args[i] = frame.attribute_utility().CreateUnknownSet(
              arg_trails[i].attribute());
        }
      }
    }

    CEL_ASSIGN_OR_RETURN(ResolveResult resolved_function,
                         resolver_.Resolve(frame, args));

    if (resolved_function.has_value() &&
        ShouldAcceptOverload(resolved_function->descriptor, args)) {
      CEL_ASSIGN_OR_RETURN(result,
                           Invoke(*resolved_function, expr_id_, args, frame));

      return absl::OkStatus();
    }

    result = NoOverloadResult(name_, args, receiver_style_, frame);

    return absl::OkStatus();
  }

  absl::optional<std::vector<const DirectExpressionStep*>> GetDependencies()
      const override {