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-rw-r--r--Lib/random.py46
1 files changed, 46 insertions, 0 deletions
diff --git a/Lib/random.py b/Lib/random.py
index 221bef6..d95c324 100644
--- a/Lib/random.py
+++ b/Lib/random.py
@@ -15,9 +15,55 @@
# Translated from anonymously contributed C/C++ source.
+import whrandom
from whrandom import random, uniform, randint, choice # Also for export!
from math import log, exp, pi, e, sqrt, acos, cos, sin
+# Interfaces to replace remaining needs for importing whrandom
+# XXX TO DO: make the distribution functions below into methods.
+
+def makeseed(a=None):
+ """Turn a hashable value into three seed values for whrandom.seed().
+
+ None or no argument returns (0, 0, 0), to seed from current time.
+
+ """
+ if a is None:
+ return (0, 0, 0)
+ a = hash(a)
+ a, x = divmod(a, 256)
+ a, y = divmod(a, 256)
+ a, z = divmod(a, 256)
+ x = (x + a) % 256 or 1
+ y = (y + a) % 256 or 1
+ z = (z + a) % 256 or 1
+ return (x, y, z)
+
+def seed(a=None):
+ """Seed the default generator from any hashable value.
+
+ None or no argument returns (0, 0, 0) to seed from current time.
+
+ """
+ x, y, z = makeseed(a)
+ whrandom.seed(x, y, z)
+
+class generator(whrandom.whrandom):
+ """Random generator class."""
+
+ def __init__(self, a=None):
+ """Constructor. Seed from current time or hashable value."""
+ self.seed(a)
+
+ def seed(self, a=None):
+ """Seed the generator from current time or hashable value."""
+ x, y, z = makeseed(a)
+ whrandom.whrandom.seed(self, x, y, z)
+
+def new_generator(a=None):
+ """Return a new random generator instance."""
+ return generator(a)
+
# Housekeeping function to verify that magic constants have been
# computed correctly