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Re: YN golf

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April 1, 2008 00:10
Re: YN golf
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On Mon, Mar 31, 2008 at 11:37:05PM -0500, Chris Dolan wrote:
> On Mar 31, 2008, at 6:54 PM, Philippe Bruhat (BooK) wrote:
>> On Mon, Mar 31, 2008 at 04:34:58PM -0700, Rick Klement wrote:
>>> perl -le 'print for glob"{Y,N}"x5'
>> Of course you have to run this in a directory that doesn't contain
>> any file matching /^[YN]{5}$/.
> Not true.  The {} notation doesn't care whether files of that name  
> actual exist.  I tested like so on Mac:

I was pretty sure I tried the same manipulation to obtain all permutations
of some series of strings, and that it didn't work as expected when one of
the permutations actually existed as a file in the current directory.

After a quick check, you are right and I was too. :-)
What I tried was:

    $ touch YYYYY
    $ perl -le 'print for glob"[YN]"x5'

I computed my permutations with square brackets (which is one character
shorter, but more fragile).

 Philippe Bruhat (BooK)

 To flaunt your strength is to make it your weakness.
                                    (Moral from Groo The Wanderer #25 (Epic))

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