[sf-perl] randomize particular lines

Quinn Weaver quinn at sf.pm.org
Tue Mar 7 09:31:01 PST 2006

On Mon, Mar 06, 2006 at 08:03:48PM -0800, Fred Moyer wrote:


> I had to get a random index from a set last week in several places in my 
> code.  I was using '$word = $words[int(rand(@words))]' (wrapped in a 
> subroutine call), but it's a fairly noisy idiom and I ended up using 
> '$word = $words[rand(@words)]' as it's a bit easier on the eyes.
> Quinn can you explain a bit more how this expression can return undef? 
> I'm using it with a defined @words list and haven't run into any 
> problems yet.

Re-running the relevant test, I believe I was mistaken.  It tried
index 2.2 on a two-element array.  Oops.

The result is undef, but that's probably the least illogical outcome in
that case.  Anyway, you wouldn't get an out-of-range value like that
from your use of rand above.

qw (Quinn Weaver); #President, San Francisco Perl Mongers
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