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-rw-r--r--Lib/random.py53
1 files changed, 10 insertions, 43 deletions
diff --git a/Lib/random.py b/Lib/random.py
index 1f3530e..a2dfcb5 100644
--- a/Lib/random.py
+++ b/Lib/random.py
@@ -282,67 +282,34 @@ class Random(_random.Random):
## -------------------- integer methods -------------------
def randrange(self, start, stop=None, step=_ONE):
- """Choose a random item from range(start, stop[, step]).
+ """Choose a random item from range(stop) or range(start, stop[, step]).
- This fixes the problem with randint() which includes the
- endpoint; in Python this is usually not what you want.
+ Roughly equivalent to ``choice(range(start, stop, step))`` but
+ supports arbitrarily large ranges and is optimized for common cases.
"""
# This code is a bit messy to make it fast for the
# common case while still doing adequate error checking.
- try:
- istart = _index(start)
- except TypeError:
- istart = int(start)
- if istart != start:
- _warn('randrange() will raise TypeError in the future',
- DeprecationWarning, 2)
- raise ValueError("non-integer arg 1 for randrange()")
- _warn('non-integer arguments to randrange() have been deprecated '
- 'since Python 3.10 and will be removed in a subsequent '
- 'version',
- DeprecationWarning, 2)
+ istart = _index(start)
if stop is None:
# We don't check for "step != 1" because it hasn't been
# type checked and converted to an integer yet.
if step is not _ONE:
- raise TypeError('Missing a non-None stop argument')
+ raise TypeError("Missing a non-None stop argument")
if istart > 0:
return self._randbelow(istart)
raise ValueError("empty range for randrange()")
- # stop argument supplied.
- try:
- istop = _index(stop)
- except TypeError:
- istop = int(stop)
- if istop != stop:
- _warn('randrange() will raise TypeError in the future',
- DeprecationWarning, 2)
- raise ValueError("non-integer stop for randrange()")
- _warn('non-integer arguments to randrange() have been deprecated '
- 'since Python 3.10 and will be removed in a subsequent '
- 'version',
- DeprecationWarning, 2)
+ # Stop argument supplied.
+ istop = _index(stop)
width = istop - istart
- try:
- istep = _index(step)
- except TypeError:
- istep = int(step)
- if istep != step:
- _warn('randrange() will raise TypeError in the future',
- DeprecationWarning, 2)
- raise ValueError("non-integer step for randrange()")
- _warn('non-integer arguments to randrange() have been deprecated '
- 'since Python 3.10 and will be removed in a subsequent '
- 'version',
- DeprecationWarning, 2)
+ istep = _index(step)
# Fast path.
if istep == 1:
if width > 0:
return istart + self._randbelow(width)
- raise ValueError("empty range for randrange() (%d, %d, %d)" % (istart, istop, width))
+ raise ValueError(f"empty range in randrange({start}, {stop})")
# Non-unit step argument supplied.
if istep > 0:
@@ -352,7 +319,7 @@ class Random(_random.Random):
else:
raise ValueError("zero step for randrange()")
if n <= 0:
- raise ValueError("empty range for randrange()")
+ raise ValueError(f"empty range in randrange({start}, {stop}, {step})")
return istart + istep * self._randbelow(n)
def randint(self, a, b):