in reply to Matching over multiple lines in a scalar

Why use negative-width assertions, when you're already using the /m flag? I like this: 

use Data::Dumper;
my $info = do { local $/; <DATA> };

my %lines;
while($info =~ m/(\d+)\: (.+?)$/gm) {
    $lines{$1} = $2;
}
print Dumper (\%lines);

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Of course, this also has an appeal: 

my %lines = $info =~ /(\d+): (.+?)$/gm;

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Passing a reference to Dumper allows Data::Dumper to dump the entire data structure without listifying it first.

Update: I miscopied the test data. Oops. Negative-width assertions are the way to go. :)

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Re: Re: Matching over multiple lines in a scalar
by thpfft (Chaplain) on Oct 27, 2002 at 23:18 UTC

    Why use negative-width assertions, when you're already using the /m flag?

    To catch the broken lines. Yours is a very elegant construction, which I intend to steal, but I don't think that snippet meets the original requirements as it is. if you knew the tags wouldn't contain numerals, which I doubt, you could change it to:

    my $info = do { local $/; <DATA> };
my %lines = $info =~ /(\d+): ([^\d]+)/gs;

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    but otherwise I can't see an alternative to the (?:^|\n).

    btw, is there any way to catch the matched values during a split? it would make this nice and tidy.

    update: damnation. redundant again.

    another update: I couldn't resist shrinking gjb's cheaper version and introducing a useful but quite unrequested array reference:

    my ($key, %data);
for (<DATA>) {
    /^(?:(\d+):\s*)*(.+)$/;
    push @{ $data{ $key = $1 || $key } }, $2;
 
}

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      Take it one step further still and do away with the temporary scalar. This works. 

      my %lines = do{local$/; <DATA> = ~m/(?:^|\n)(\d+)\:(.+?)(?=(?:\n\d)|$)
+/gs };

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      Now I'll wait for sauoq to reduce the regex to 3 chars and a twiddle and we've got a golf solution.:^)

      Nah! Your thinking of Simon Templar, originally played by Roger Moore and later by Ian Ogilvy
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        after a tactful /msg from chromatic, i can confirm that this works too, provided the data are very tidy indeed.

        (i wish someone would redefine data as the mass noun it surely is, then I could stop pedantically pluralising around it.)

        my (undef, %lines) = split(/(\d+): /, join('', <DATA>));

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        ugly, fragile and unwise, but you know, short.

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Re: Re: Matching over multiple lines in a scalar
by BrowserUk (Patriarch) on Oct 27, 2002 at 22:58 UTC

    That doesn't work for the first and last 'lines' which actually each consist of 2 lines.

    Nah! Your thinking of Simon Templar, originally played by Roger Moore and later by Ian Ogilvy
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