Method evalSpecialForm

bolt/expression/LambdaExpr.cpp:199–232

}

void LambdaExpr::evalSpecialForm(
    const SelectivityVector& rows,
    EvalCtx& context,
    VectorPtr& result) {
  if (!typeWithCapture_) {
    makeTypeWithCapture(context);
  }
  std::vector<VectorPtr> values(typeWithCapture_->size());
  for (auto i = 0; i < captureChannels_.size(); ++i) {
    assert(!values.empty());
    // Ensure all captured fields are loaded.
    const auto& rowsToLoad =
        context.isFinalSelection() ? rows : *context.finalSelection();
    context.ensureFieldLoaded(captureChannels_[i], rowsToLoad);
    values[signature_->size() + i] = context.getField(captureChannels_[i]);
  }
  auto capture = std::make_shared<RowVector>(
      context.pool(),
      typeWithCapture_,
      BufferPtr(nullptr),
      rows.end(),
      values,
      0);
  auto callable = std::make_shared<ExprCallable>(signature_, capture, body_);
  std::shared_ptr<FunctionVector> functions;
  if (!result) {
    functions = std::make_shared<FunctionVector>(context.pool(), type_);
    result = functions;
  } else {
    BOLT_CHECK(result->encoding() == VectorEncoding::Simple::FUNCTION);
    functions = std::static_pointer_cast<FunctionVector>(result);
  }
  functions->addFunction(callable, rows);
}

void LambdaExpr::makeTypeWithCapture(EvalCtx& context) {
  // On first use, compose the type of parameters + capture and set