Debugging (was Re: Why not allow empty code blocks?)

[Terry Reedy]

Making repeat a keyword would have such an extremely high cost
that it is out of the question and not a sane proposal.
To start with, it is used in two major, widely used APIs.

itertools.repeat + 50 uses in other itertools and tests
  + all the imports and and uses of repeat()
  in code all over the world.

timeit command line option
timeit.timeit(..., repeat=3) parameter name
timeit.repeat() function  + tests
  + all the scripts (some in other languages) using 'repeat'
  as a command line option and all the python code using
  the parameter or function.

There are other C-coded public APIs that use repeat.  One in xml.etree 
was revealed by the grep hit for the Python-coded test.

Other places in the *Python-coded* stdlib that would break.

distutils\fancy_getopt.py: 141:         self.repeat = {}
lib2to3\fixes\fix_operator.py: 8: operator.repeat(obj, n) ...
lib2to3\patcomp.py: 105:         repeat = None
lib2to3\patcomp.py: 139: def compile_basic(self, nodes, repeat=None):
lib2to3\tests\test_fixers.py: 4494:         b = "operator.repeat(x, n)"
test\test_faulthandler.py: 533:             repeat = {repeat}
test\test_faulthandler.py: 539:     def func(timeout, repeat, ...
test\test_xml_etree.py: 1784:      for dumper, loader in 
product(self.modules, repeat=2):
typing.py: 373:       def repeat(x: T, n: int) -> Sequence[T]:

-- 
Terry Jan Reedy