Move all file-load code into iris.io.loading.

lib/iris/cube.py

@@ -60,89 +60,6 @@
 XML_NAMESPACE_URI = "urn:x-iris:cubeml-0.2"
 
 
-class _CubeFilter:
-    """A constraint, paired with a list of cubes matching that constraint."""
-
-    def __init__(self, constraint, cubes=None):
-        self.constraint = constraint
-        if cubes is None:
-            cubes = CubeList()
-        self.cubes = cubes
-
-    def __len__(self):
-        return len(self.cubes)
-
-    def add(self, cube):
-        """Add the appropriate (sub)cube to the list of cubes where it matches the constraint."""
-        sub_cube = self.constraint.extract(cube)
-        if sub_cube is not None:
-            self.cubes.append(sub_cube)
-
-    def combined(self, unique=False):
-        """Return a new :class:`_CubeFilter` by combining the list of cubes.
-
-        Combines the list of cubes with :func:`~iris._combine_load_cubes`.
-
-        Parameters
-        ----------
-        unique : bool, default=False
-            If True, raises `iris.exceptions.DuplicateDataError` if
-            duplicate cubes are detected.
-
-        """
-        from iris import _combine_load_cubes
-
-        return _CubeFilter(
-            self.constraint,
-            _combine_load_cubes(self.cubes, merge_require_unique=unique),
-        )
-
-
-class _CubeFilterCollection:
-    """A list of _CubeFilter instances."""
-
-    @staticmethod
-    def from_cubes(cubes, constraints=None):
-        """Create a new collection from an iterable of cubes, and some optional constraints."""
-        constraints = iris._constraints.list_of_constraints(constraints)
-        pairs = [_CubeFilter(constraint) for constraint in constraints]
-        collection = _CubeFilterCollection(pairs)
-        for c in cubes:
-            collection.add_cube(c)
-        return collection
-
-    def __init__(self, pairs):
-        self.pairs = pairs
-
-    def add_cube(self, cube):
-        """Add the given :class:`~iris.cube.Cube` to all of the relevant constraint pairs."""
-        for pair in self.pairs:
-            pair.add(cube)
-
-    def cubes(self):
-        """Return all the cubes in this collection in a single :class:`CubeList`."""
-        from iris.cube import CubeList
-
-        result = CubeList()
-        for pair in self.pairs:
-            result.extend(pair.cubes)
-        return result
-
-    def combined(self, unique=False):
-        """Return a new :class:`_CubeFilterCollection` by combining all the cube lists of this collection.
-
-        Combines each list of cubes using :func:`~iris._combine_load_cubes`.
-
-        Parameters
-        ----------
-        unique : bool, default=False
-            If True, raises `iris.exceptions.DuplicateDataError` if
-            duplicate cubes are detected.
-
-        """
-        return _CubeFilterCollection([pair.combined(unique) for pair in self.pairs])
-
-
 class CubeList(list):
     """All the functionality of a standard :class:`list` with added "Cube" context."""