in reply to Regexp help

Seems to me this would be quite easy to implement reading a line at a time. Just keep a flag indicating whether you should be indenting or not. 

while (<>) {
   if    ( /^Heading Here:/    ) { $_ = "\n" . $_; $indent = 1; }
   elsif ( /^Another Heading:/ ) { $indent = 1; }
   elsif ( /^End of section:/  ) { $indent = 0; }
   elsif ( $indent             ) { $_ = "  " . $_; }

   print;
}

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Re^2: Regexp help
by Kc12349 (Monk) on Sep 16, 2011 at 19:45 UTC

    I agree. I might even take it a step further and write it with an eye for maintainability and allow myself to easily add new headings as needed.

    my @new_line_strings = (
   'Heading Here',
   );
my @opening_strings = (
   'Heading Here',
   'Another Heading',
   );
my @closing_strings = (
   'End of section',
   @opening_strings,
   );

my $new_line_pattern = '^(?:' . join('|', @new_line_strings) . ')';
my $opening_pattern = '^(?:' .  join('|', @opening_strings) . ')';
my $closing_pattern = '^(?:' .  join('|', @closing_strings) . ')';
   
while ( defined (my $line = <DATA> ) )
{
   state $indent_char = '';
   $indent_char = '' if $line =~ m/$closing_pattern/;
   print "\n" if $line =~ m/$new_line_pattern/;
   print $indent_char . $line;
   $indent_char = '  ' if $line =~ m/$opening_pattern/;
}

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[d/l]

      This tweak adds a newline to the first heading in a series:

      while ( defined (my $line = <DATA> ) )
{
   state $indent_char = '';
   print "\n" if $line =~ m/$opening_pattern/ && ! $indent_char;
   $indent_char = '' if $line =~ m/$closing_pattern/;
   print $indent_char . $line;
   $indent_char = '  ' if $line =~ m/$opening_pattern/;
}

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[d/l]
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