in reply to Re: Re: Re: Find common prefix from a list of strings
in thread Find common prefix from a list of strings

There's another case this will fail for:

@files = qw(model4run1 model2run1 model4run2 abbot);
...
print Jenda(@files),$/;
__DATA__
model4

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antirice    
The first rule of Perl club is - use Perl
The ith rule of Perl club is - follow rule i - 1 for i > 1

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Re: Re: Re: Re: Re: Find common prefix from a list of strings
by Jenda (Abbot) on Jul 15, 2003 at 12:09 UTC

    Whadaheck?
    ...
    The problem was in the 

    $combined =~ s/[^\x00].*//;

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    I tried to print the variable with</code> print "\$combined=",unpack("H*",$combined)," ($combined)\n"; </code> and was really surprised:
    ¢¼combined=0c0d060a183672756e33 (”Ļ
”č6run3)
$combined=0a183672756e33 (
”č6run3)
Prefix is "model4r"

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    (I'd be even more surprised if this went through correctly.)

    Guess what was the problem ... well the .* did not match everything. I forgot that without /s dot doesn't match newlines. So the fix is very simple

    ...
$combined =~ s/[^\x00].*//s;
...

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    Actually thinking about this it would probably be better to change the last three lines to:
    $combined =~ /^(\x00*)/;
my $prefix = substr($first, 0, length($1));
print qq{Prefix is "$prefix"};

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    I should have tested my code better :-(

    Jenda
    Always code as if the guy who ends up maintaining your code will be a violent psychopath who knows where you live.
       -- Rick Osborne

    Edit by castaway: Closed small tag in signature

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