Syntactic Sugar for Templated Classes

[kwabenantim]

Summary

Add a way to use instantiated C++ template classes from Python that looks a bit more like the C++ syntax.

For example:

# This:
simulation = OffLatticeSimulation2_2(cell_population)

# would become:
simulation = OffLatticeSimulation[2][2](cell_population)

# and this:
cell_population = VertexBasedCellPopulation2(mesh, cells)

# would become:
cell_population = VertexBasedCellPopulation[2](mesh, cells)

[kwabenantim]

One possible solution with dicts:

OffLatticeSimulation = {2: {2: OffLatticeSimulation2_2}}

VertexBasedCellPopulation = {2: VertexBasedCellPopulation2}

[kwabenantim]

Perhaps override [] and use numpy-like indexing so we can have:

simulation = OffLatticeSimulation[2, 2](cell_population)

[mirams]

I like that, as long as it isn't too confusing in looking like an array, but makes a lot of sense compared to the ones above!

[kwabenantim]

One possible solution could be:

class TemplateClassDict:
  def __init__(self, template_dict):
    self._dict = template_dict

  def __getitem__(self, key):
      return self._dict[key]

OffLatticeSimulation = TemplateClassDict(
  {
    (2, 2): OffLatticeSimulation_2_2,
    (3, 3): OffLatticeSimulation_3_3,
  }
)

Which can be used like

simulation = OffLatticeSimulation[2, 2](cell_population)

[kwabenantim]

This has been implemented as:

class TemplateClassDict:

    def __init__(self, template_dict):
        self._dict = {}
        for arg_tuple, cls in template_dict.items():
            if not inspect.isclass(cls):
                raise TypeError("Expected class, got {}".format(type(cls)))
            if not isinstance(arg_tuple, Iterable):
                arg_tuple = (arg_tuple,)
            key = tuple(
                arg.__name__ if inspect.isclass(arg) else str(arg) for arg in arg_tuple
            )
            self._dict[key] = cls

    def __getitem__(self, arg_tuple):
        if not isinstance(arg_tuple, Iterable):
            arg_tuple = (arg_tuple,)
        key = tuple(
            arg.__name__ if inspect.isclass(arg) else str(arg) for arg in arg_tuple
        )
        return self._dict[key]

An example of this is:

CellsGenerator = TemplateClassDict(
  {
    ("AlwaysDivideCellCycleModel", "2"): CellsGenerator_AlwaysDivideCellCycleModel_2,
    ("AlwaysDivideCellCycleModel", "3"): CellsGenerator_AlwaysDivideCellCycleModel_3,
    ("BernoulliTrialCellCycleModel", "2"): CellsGenerator_BernoulliTrialCellCycleModel_2,
    ("BernoulliTrialCellCycleModel", "3"): CellsGenerator_BernoulliTrialCellCycleModel_3,
  }
)

Which can be used like:

gen = CellsGenerator["AlwaysDivideCellCycleModel", "2"]()  # recommended

# OR
gen = CellsGenerator["AlwaysDivideCellCycleModel", 2]()

# OR
gen = CellsGenerator[AlwaysDivideCellCycleModel, "2"]()

# OR
gen = CellsGenerator[AlwaysDivideCellCycleModel, 2]()