def test():
'''Test the basic workings of `get_length`.'''
assert get_length(range(3)) == 3
assert get_length(xrange(4)) == 4
assert get_length(set(xrange(5))) == 5
assert get_length(iter(set(xrange(16, 10, -1)))) == 6
def test():
'''Test the basic workings of `get_length`.'''
assert get_length(list(range(3))) == 3
assert get_length(range(4)) == 4
assert get_length(set(range(5))) == 5
assert get_length(iter(set(range(16, 10, -1)))) == 6
def get_n_identical_edge_characters(string, character=None, head=True):
'''
Get the number of identical characters at `string`'s head.
For example, the result for 'qqqwe' would be `3`, while the result for
'meow' will be `1`.
Specify `character` to only consider that character; if a different
character is found at the head, `0` will be returned.
Specify `head=False` to search the tail instead of the head.
'''
from python_toolbox import cute_iter_tools
if not string:
return 0
found_character, character_iterator = next(
itertools.groupby(string if head else reversed(string)))
if (character is not None) and found_character != character:
assert isinstance(character, str) and len(character) == 1
return 0
return cute_iter_tools.get_length(character_iterator)
def get_n_identical_edge_characters(string, character=None, head=True):
'''
Get the number of identical characters at `string`'s head.
For example, the result for 'qqqwe' would be `3`, while the result for
'meow' will be `1`.
Specify `character` to only consider that character; if a different
character is found at the head, `0` will be returned.
Specify `head=False` to search the tail instead of the head.
'''
from python_toolbox import cute_iter_tools
if not string:
return 0
found_character, character_iterator = next(
itertools.groupby(string if head else reversed(string))
)
if (character is not None) and found_character != character:
assert isinstance(character, str) and len(character) == 1
return 0
return cute_iter_tools.get_length(character_iterator)
def __init__(self, slice_, iterable_or_length=None, offset=0):
from python_toolbox import sequence_tools
from python_toolbox import cute_iter_tools
if isinstance(slice_, CanonicalSlice):
slice_ = slice(slice_.start, slice_.stop, slice_.step)
assert isinstance(slice_, slice)
self.given_slice = slice_
if iterable_or_length is not None:
if isinstance(iterable_or_length,
math_tools.PossiblyInfiniteIntegral):
self.length = iterable_or_length
elif isinstance(iterable_or_length, collections.Sequence):
self.length = sequence_tools.get_length(iterable_or_length)
else:
assert isinstance(iterable_or_length, collections.Iterable)
self.length = cute_iter_tools.get_length(iterable_or_length)
else:
self.length = None
self.offset = offset
### Parsing `step`: ###################################################
# #
assert slice_.step != 0
if slice_.step is None:
self.step = 1
else:
self.step = slice_.step
# #
### Finished parsing `step`. ##########################################
### Parsing `start`: #################################################
# #
if slice_.start is None:
if self.step > 0:
self.start = 0 + self.offset
else:
assert self.step < 0
self.start = (self.length + self.offset) if \
(self.length is not None) else infinity
else: # s.start is not None
if self.length is not None:
if slice_.start < 0:
self.start = \
max(slice_.start + self.length, 0) + self.offset
else:
self.start = min(slice_.start, self.length) + self.offset
else:
self.start = slice_.start + self.offset
# #
### Finished parsing `start`. #########################################
### Parsing `stop`: ###################################################
# #
if slice_.stop is None:
if self.step > 0:
self.stop = (self.length + self.offset) if \
(self.length is not None) else infinity
else:
assert self.step < 0
self.stop = -infinity
else: # slice_.stop is not None
if self.length is not None:
if slice_.stop < 0:
self.stop = max(slice_.stop + self.length, 0) + self.offset
else: # slice_.stop >= 0
self.stop = min(slice_.stop, self.length) + self.offset
else:
self.stop = slice_.stop + self.offset
# #
### Finished parsing `stop`. ##########################################
if (self.step > 0 and self.start >= self.stop >= 0) or \
(self.step < 0 and self.stop >= self.start):
# We have a case of an empty slice.
self.start = self.stop = 0
self.slice_ = slice(
*((item if item not in math_tools.infinities else None)
for item in self))
### Doing sanity checks: ##############################################
# #
if self.length:
if self.step > 0:
assert 0 <= self.start <= \
self.stop <= self.length + self.offset
else:
assert self.step < 0
assert 0 <= self.stop <= \
self.start <= self.length + self.offset
def __init__(self, slice_, iterable_or_length=None, offset=0):
from python_toolbox import sequence_tools
from python_toolbox import cute_iter_tools
if isinstance(slice_, CanonicalSlice):
slice_ = slice(slice_.start, slice_.stop, slice_.step)
assert isinstance(slice_, slice)
self.given_slice = slice_
if iterable_or_length is not None:
if isinstance(iterable_or_length,
math_tools.PossiblyInfiniteIntegral):
self.length = iterable_or_length
elif isinstance(iterable_or_length, collections.Sequence):
self.length = sequence_tools.get_length(iterable_or_length)
else:
assert isinstance(iterable_or_length, collections.Iterable)
self.length = cute_iter_tools.get_length(iterable_or_length)
else:
self.length = None
self.offset = offset
### Parsing `step`: ###################################################
# #
assert slice_.step != 0
if slice_.step is None:
self.step = 1
else:
self.step = slice_.step
# #
### Finished parsing `step`. ##########################################
### Parsing `start`: #################################################
# #
if slice_.start is None:
if self.step > 0:
self.start = 0 + self.offset
else:
assert self.step < 0
self.start = (self.length + self.offset) if \
(self.length is not None) else infinity
else: # s.start is not None
if self.length is not None:
if slice_.start < 0:
self.start = \
max(slice_.start + self.length, 0) + self.offset
else:
self.start = min(slice_.start, self.length) + self.offset
else:
self.start = slice_.start + self.offset
# #
### Finished parsing `start`. #########################################
### Parsing `stop`: ###################################################
# #
if slice_.stop is None:
if self.step > 0:
self.stop = (self.length + self.offset) if \
(self.length is not None) else infinity
else:
assert self.step < 0
self.stop = -infinity
else: # slice_.stop is not None
if self.length is not None:
if slice_.stop < 0:
self.stop = max(slice_.stop + self.length, 0) + self.offset
else: # slice_.stop >= 0
self.stop = min(slice_.stop, self.length) + self.offset
else:
self.stop = slice_.stop + self.offset
# #
### Finished parsing `stop`. ##########################################
if (self.step > 0 and self.start >= self.stop >= 0) or \
(self.step < 0 and self.stop >= self.start):
# We have a case of an empty slice.
self.start = self.stop = 0
self.slice_ = slice(*((item if item not in math_tools.infinities
else None) for item in self))
### Doing sanity checks: ##############################################
# #
if self.length:
if self.step > 0:
assert 0 <= self.start <= \
self.stop <= self.length + self.offset
else:
assert self.step < 0
assert 0 <= self.stop <= \
self.start <= self.length + self.offset
