From: redmine@...
Date: 2011-04-20T23:31:07+09:00
Subject: [ruby-core:35833] [Ruby 1.9 - Bug #4590][Open] documentation is wrong for srand


Issue #4590 has been reported by Cezary Baginski.

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Bug #4590: documentation is wrong for srand
http://redmine.ruby-lang.org/issues/4590

Author: Cezary Baginski
Status: Open
Priority: Low
Assignee: 
Category: core
Target version: 
ruby -v: r31311


'ri srand' (in random.c) suggests that passing 0 generates a seed number:

 If <i>number</i> is omitted *or zero*, seeds the generator using a combination of (...)}

Currently, this isn't true (0 is a valid seed):
 >> srand(10); srand; srand
 => 290577086691033874500011807841900203857
 >> srand(10); srand(0); srand(0)
 => 0

 
It should be:

 If <i>number</i> is omitted, seeds the generator using a combination of (...)

I would normally create a patch for this, but wouldn't it be less surprising if srand accepted nil for generating the random seed?


Instead of code like:

 prev_seed = (seed == nil ? srand : srand(seed))

we would have:

 prev_seed = srand(seed)

Would this be a good idea?

Currently this fails, because an integer is expected:

 >> srand(nil)
 TypeError: can't convert nil into Integer




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