Re: Re (tilly) 1: (Golf) Strings-to-Array

So if I was a careless lout, I could claim 28, but I am not...

sub r {my$s;$s.=chop for@_=@_;$s.0?(&r,$s):()}
[download]

Tilly, I have tested your line as follows

  sub r {my$s;$s.=chop for@_;$s?(&r,$s):()}

        #0        1         2         3  3
        #123456789012345678901234567890123

  # jeff,john,mary
  # jjm,eoa,fhr,fny
[download]

on v5.6.1-AS628. and it worked fine.

I suppose I am missing something, but I dont see what.
Why are you doing @_=@_ and $s.0??
Is this an issue for an earlier version of perl? As far as I understand these are redundant ops. When does $s.0 evalute in a boolean sense different to $s? And what is the point of assigning @_ to itself?
I am confused.

OTOH it does mean that you can claim 5 less chars, for a total of 33.
:-)
Or am I being a lout?

Yves

Comment on Re: Re (tilly) 1: (Golf) Strings-to-Array Select or Download Code

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Re (tilly) 3: (Golf) Strings-to-Array by tilly (Archbishop) on Sep 01, 2001 at 05:13 UTC
In Perl 5.6.0 if you passed in literal strings, you got an error about, "Modification of a read-only value attempted". Recopying @_ fixed that. And the time when $s and $s.0 are different in boolean context is when $s is "0". So when you remove those two characters, you get a bug. UPDATE An example that shows the bug: `print map "$_\n", r("0a1", "b0", "0");` [download]	[reply] [d/l]
Re: Re (tilly) 3: (Golf) Strings-to-Array by demerphq (Chancellor) on Sep 01, 2001 at 18:27 UTC
Hi Tilly. Ok so on that input it doesnt work. I guess now I'm being a pain, but japhy's spec did say make a function that takes any number of equal-length* strings* However I do believe in defensive programming, so I can see why you did that. Very interesting, and food for thought Yves `$\="\n"; $,=","; print r("0000", "0000", "0000"); #outputs #000,000,000,000` [download]	[reply] [d/l]
Re (tilly) 5: (Golf) Strings-to-Array by tilly (Archbishop) on Sep 03, 2001 at 03:38 UTC
And what happens if you call r('0000')? Any number includes 1. :-)	[reply]
Re: Re (tilly) 3: (Golf) Strings-to-Array by demerphq (Chancellor) on Sep 01, 2001 at 05:37 UTC
Hmm, and I reran it with literal params (I was using an @array) and I got that warnings as well. Interesting. OST. It follows from the fact @_ alises not copies, but still somehow surprising. And it is also very interesting to learn that '00' evals to true. Definitely not what I expected. I was thinking that it would fall under the evals to 0 rule, but now I see not. Thanx. On the other hand I tested a bunch of cases with 0's in them and I couldnt see how it affected the solution? Yves	[reply]


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