Converting the steps from a shell pipeline to Perl is fairly easy. The steps are:

  1. grep Acct: Facs_Data.txt - Read a file line by line and select the lines matching Acct:
  2. cut -d":" -f2 - Take the side to the right of : of the line
  3. cut -d" " -f1 - take the side to the left of the blank of the line

If we convert each step to Perl, we get the following parts:

  1. my $filename = 'Facs_Data.txt';
open my $fh, '<', $filename
    or die "Couldn't open '$filename': $!";

my @lines = grep { /Acct:/ } <$fh>; # Read a file line by line and sel
+ect the lines matching Acct:

    [download]
  2. @lines = map { [ split $_, /:/ ]->[1] } @lines; # Take the side to the
+ right of : of the line

    [download]
  3. @lines = map { [ split $_, /:/ ]->[0] } @lines; # take the side to the
+ left of the blank of the line

    [download]

But a more perlish approach would be to do all that in one go:

my $filename = 'Facs_Data.txt';
open my $fh, '<', $filename
    or die "Couldn't open '$filename': $!";

my @lines = map  { /:([^\s]+)/ ? $1 : () } # take the stuff between th
+e : and the first blank
            grep { /Acct:/ } <$fh>; # Read a file line by line and sel
+ect the lines matching Acct:

# do whatever with the values in @lines
print "$_\n" for @lines;

[download]

Update:: Fixed missing = in step three, spotted by AnomalousMonk, thanks.

In reply to Re: How do I use grep in a script by Corion
in thread How do I use grep in a script by Flintlock

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