implement ndarray.flat.__getitem__(slice)

[sklam]

Feature request

From gitter: https://gitter.im/numba/numba?at=5df10b072cc1b31e34fee7dc
Related #3120

Feature request for ndarray.flat.__getitem__(slice)

Associated lowering code:

numba/numba/targets/arrayobj.py

Lines 3134 to 3207 in 3ee0556

	@lower_getattr(types.Array, "flat")
	def make_array_flatiter(context, builder, arrty, arr):
	flatitercls = make_array_flat_cls(types.NumpyFlatType(arrty))
	flatiter = flatitercls(context, builder)
	flatiter.array = arr
	arrcls = context.make_array(arrty)
	arr = arrcls(context, builder, ref=flatiter._get_ptr_by_name('array'))
	flatiter.init_specific(context, builder, arrty, arr)
	res = flatiter._getvalue()
	return impl_ret_borrowed(context, builder, types.NumpyFlatType(arrty), res)
	@lower_builtin('iternext', types.NumpyFlatType)
	@iternext_impl(RefType.BORROWED)
	def iternext_numpy_flatiter(context, builder, sig, args, result):
	[flatiterty] = sig.args
	[flatiter] = args
	flatitercls = make_array_flat_cls(flatiterty)
	flatiter = flatitercls(context, builder, value=flatiter)
	arrty = flatiterty.array_type
	arrcls = context.make_array(arrty)
	arr = arrcls(context, builder, value=flatiter.array)
	flatiter.iternext_specific(context, builder, arrty, arr, result)
	@lower_builtin(operator.getitem, types.NumpyFlatType, types.Integer)
	def iternext_numpy_getitem(context, builder, sig, args):
	flatiterty = sig.args[0]
	flatiter, index = args
	flatitercls = make_array_flat_cls(flatiterty)
	flatiter = flatitercls(context, builder, value=flatiter)
	arrty = flatiterty.array_type
	arrcls = context.make_array(arrty)
	arr = arrcls(context, builder, value=flatiter.array)
	res = flatiter.getitem(context, builder, arrty, arr, index)
	return impl_ret_borrowed(context, builder, sig.return_type, res)
	@lower_builtin(operator.setitem, types.NumpyFlatType, types.Integer,
	types.Any)
	def iternext_numpy_getitem_any(context, builder, sig, args):
	flatiterty = sig.args[0]
	flatiter, index, value = args
	flatitercls = make_array_flat_cls(flatiterty)
	flatiter = flatitercls(context, builder, value=flatiter)
	arrty = flatiterty.array_type
	arrcls = context.make_array(arrty)
	arr = arrcls(context, builder, value=flatiter.array)
	flatiter.setitem(context, builder, arrty, arr, index, value)
	return context.get_dummy_value()
	@lower_builtin(len, types.NumpyFlatType)
	def iternext_numpy_getitem_flat(context, builder, sig, args):
	flatiterty = sig.args[0]
	flatitercls = make_array_flat_cls(flatiterty)
	flatiter = flatitercls(context, builder, value=args[0])
	arrcls = context.make_array(flatiterty.array_type)
	arr = arrcls(context, builder, value=flatiter.array)
	return arr.nitems

[duburcqa]

Any update on this ? Having this feature implemented would be very handy.