Re: What is the fastest way to extract data from a delimited string?

... yet another way

use strict;

my (@list) = map { /\w+\s+\w+\s+\w+\s+\w+\s+\w+\s+(\w+)\s+.*/} <DATA>;

print "@list";

__DATA__
1    2    3    4    5    6    7    8
james joe jack janet jill joann joeanne bill bob
alice joe jack janet jill alice joeanne bill bob
james joe jack janet jill susan joeanne bill bob
james joe jack janet jill sarah joeanne bill bob
james joe jack janet jill ethel joeanne bill bob
[download]

Only using map... very brief though :)

Comment on Re: What is the fastest way to extract data from a delimited string? Download Code

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Re: Re: What is the fastest way to extract data from a delimited string? by dragonchild (Archbishop) on Jan 10, 2003 at 15:49 UTC
Not very fast or maintenable, though. How about something like: `sub read_stuff { my ($handle, $delim, $col) = @_; my $prep = '^\s'; $prep .= "\w+${delim}+" for 1 .. $col - 1; $prep .= "(\w+)(?:${delim}\|$)"; my $regex = qr/$prep/; my @list = map { /$regex/o } <$handle>; return @list; } my $handle = IO::File->new(filename => "some_file"); my @list = read_stuff($handle, ' ', 6);` [download] Remember something - "fast" is a relative term. You might squeeze an additional millisecond from your CPU, but require an extra 8 hours every time you want to make a change to your code. To me, that's not worth it. My 8 hours is worth more than one millisecond of CPU time. To me, "fast" has to do with acceptable CPU progress and lightning-quick maintenance time. YMMV. ------ We are the carpenters and bricklayers of the Information Age.* Don't go borrowing trouble. For programmers, this means Worry only about what you need to implement.	[reply] [d/l]

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Re: Re: What is the fastest way to extract data from a delimited string?
by dragonchild (Archbishop) on Jan 10, 2003 at 15:49 UTC

sub read_stuff
{
    my ($handle, $delim, $col) = @_;

    my $prep = '^\s*';
    $prep .= "\w+${delim}+" for 1 .. $col - 1;
    $prep .= "(\w+)(?:${delim}|$)";
    my $regex = qr/$prep/;
    my @list = map { /$regex/o } <$handle>;

    return @list;
}

my $handle = IO::File->new(filename => "some_file");
my @list = read_stuff($handle, ' ', 6);
[download]

------
We are the carpenters and bricklayers of the Information Age.

Don't go borrowing trouble. For programmers, this means Worry only about what you need to implement.

[reply]
[d/l]