[email protected] wrote:
> I have a single input file with entries as follows:
>
> --snip--
> USER1 [20090101] note
> bla bla bla
> bla bla bla
>
> USER2 [20090104] note
> bla bla bla
> bla bla bla
>
> --snip--
>
> What I'm trying to do is create a single-argument script which displays
> all entries for a given user.
>
> So calling it as 'filter.pl user1' will print all entries for USER1.
>
>
> Here is what I've got so far:
>
> ---
> my $user = shift;
>
> # slurp file
> my $file = do {
> open my $fh, 'inputfile.txt' or die $!;
> local $/;
> <$fh>;
> };
>
> if ( $file =~ /(^$user.*?)^$/smg ) {
> print $1;
> }
> ---
>
> Here's my thinking behind the non-functional regex.
> It matches a set of lines starting with a line which begins with $user,
> followed by all non-empty lines, and terminated with an empty line (^$).
>
> Running my script produces zero output. My questions are:
> 1. Is there a simpler way to approach/accomplish this?
> 2. If not, what's wrong with my regex?
>
>
>
> Thanks in advance for any help.
I don't kno what results you're getting, but this works fine for me. The only
change I would make is to change the 'if' to a 'while', otherwise only the first
matching record will be found.
There may be an issue with reading the entire file if it is at all large, in
which case I recommend reading in 'paragraph' mode by setting the input record
separator to the null string
local $/ = "";
after which each read from the file will return a single complete multi-line
record, terminated by a blank line.
HTH,
Rob
use strict;
use warnings;
my $user = 'USER1';
# slurp file
my $file = do {
local $/;
<DATA>;
};
if ( $file =~ /(^$user.*?)^$/smg ) {
print $1;
}
__DATA__
USER1 [20090101] note
bla bla bla
bla bla bla
USER2 [20090104] note
bla bla bla
bla bla bla
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