Add `ListTagRemoveIf`

It is sometimes useful to remove types from ListTags. This is especially the case when combining lists of types together where some of the type combinations may be invalid and should be removed. To handle this situation, a new ListTag type is added: ListTagRemoveIf.

ListTagRemoveIf is a template structure that takes two arguments. The first argument is another ListTag type to operate on. The second argument is a template that acts as a predicate. The predicate takes a type and declares a Boolean value that should be true if the type should be removed and false if the type should remain.

Here is an example of using ListTagRemoveIf to get basic types that hold only integral values.

template <typename T>
using IsRealValue =
  std::is_same<
    typename vtkm::TypeTraits<typename vtkm::VecTraits<T>::BaseComponentType>::NumericTag,
    vtkm::TypeTraitsRealTag>;

using MixedTypes =
  vtkm::ListTagBase<vtkm::Id, vtkm::FloatDefault, vtkm::Id3, vtkm::Vec3f>;

using IntegralTypes = vtkm::ListTagRemoveIf<MixedTypes, IsRealValue>;
// IntegralTypes now equivalent to vtkm::ListTagBase<vtkm::Id, vtkm::Id3>

1.1 KiB Raw Blame History

Add ListTagRemoveIf

1.1 KiB

Raw Blame History

Add `ListTagRemoveIf`