SPUG: reg exp's

[Jim Flanagan]

On Tue, 3 Sep 2002, Baker, Stephen M wrote:

> 
> I need to parse quickly through a file of the following format:
> 
> heading1: data1.1
> heading2: data2.1
> heading3: data3.1
> 
> heading1: data1.2
> heading2: data2.2
> heading3: data3.2
> 
> heading1: data1.3
> heading2: data2.3
> heading3: data3.3
> 
> to populate a data structure.  Is regular expressions the way to go about
> this? OR does somebody have a trick for how this might be done?

Since it appears that the pattern is simple, you can use split here. 

  use FileHandle;

  my %datahash;
  my $fh = new FileHandle("<datafile");
  die "Error opening file: $!\n" unless defined $fh;

  while(my $line = <$fh>) {
    next if $line =~ /^$/;
    my ($k, $v) = split(/:\s+/, $line);
    die "Error in datafile\n" unless data_seems_reasonable($k, $v);
    push @{$datahash{$v}}, $v;
  }
    
  close $fh;

  do_something_with($datahash{heading1}->[0]);

  for my $h2 (@{$datahash{heading2}}) {
    do_something_else($h2)
  }

-- 
Flanagan::Jim

    http://jimfl.tensegrity.net
  mailto:jimfl%40t%65ns%65gr%69ty.n%65t



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