def merge_values(mergeables_out: Iterable, mergeables_in: Iterable) -> Iterable:
"""
Merge values of second argument into values of first argument and return
first argument.
"""
if mergeables_out is not None and mergeables_in is not None:
for mergeable_out, mergeable_in in zip(mergeables_out, mergeables_in):
Utils.merge_values(mergeable_out, mergeable_in)
elif mergeables_out is None and mergeables_in is not None:
mergeables_out = mergeables_in
# This should treat the 4 possible cases:
# 1. both arguments are non-empty: first if statement
# 2. First argument is None and second is not empty: elif statement
# 3. First argument is not empty and second is None: return first
# list, no need to do anything
# 4. Both arguments are None: return first, it's None anyway.
return mergeables_out
def reducer(mergeables_out, mergeables_in):
"""
Merges two given lists of values that were
returned by the mapper function for two different
ranges.
Args:
mergeables_out (list): A list of computed (mergeable)values for
a given entry range in a dataset. The elements of this list
will be updated with the information contained in the
elements of the other argument list.
mergeables_in (list): A list of computed (mergeable)values for
a given entry range in a dataset.
Returns:
list: The list of updated (mergeable)values.
"""
for mergeable_out, mergeable_in in zip(mergeables_out,
mergeables_in):
Utils.merge_values(mergeable_out, mergeable_in)
return mergeables_out