-- Randal L. Schwartz, Perl hacker

Do two operations: split on /\s*\([a-zA-Z1-90]*\)/ in @texts, and then do a /\s*\(([a-zA-Z1-90]*)\)/g into @sections. Shift off the first element of @texts (should be whatever comes before the first section indicator, which you suggest is null), and then for array element $i, $texts[$i] corresponds to $section[$i].

Now, you simply need to work out the tree structure for this. Create an array of subroutines that parse the appropriate section number at the given level. Eg:

sub major_section { 
   $sec = shift;
   if ( $sec =~ /^([A-Z])$/ ) {
       return ( ord $1 - ord 'A' + 1 );
   } else {
       return 0;
   }
}
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The only problem is a case like the following:

A.
  1.
  2.
    a.
       1. list data
       2. list data
  3. 
  4.
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without more formal guidelines from the original format, you will not be able to determin where A.2.a's list stops and section A.3 begins.

Which is pretty much my problem...the original format is written for humans to read (well, politicians), so as far as I can tell there is no syntactical help, which is why I was hoping for an overarching parser to check for all errors on assumptions, but I can see that that isn't going to handle all cases.

Back to the drawing board I guess.

• read all "(marker) associated text" blocks into a hash
• parse hash keys with rules to work out placement
• create new node hash to show parentage

ie

# use this in your rule tests for position
my %structure = (
  1 => {qw(a b c d e f g h i etc...)},
  2 => {qw(1 2 3 4 5 6 7 8 9 10 11 12 13 etc...)},
  3 => {qw(A B C D E F G H I etc...)},
  4 => {qw(i ii iii iv v vi vii viii ix x xi etc...)}
  );

my %legalese; # hash to store text/markers
my $key = 2;  # key marker to keep order ('1' is tree root)

# read into hash
while (s/\((\w+)\)(.*?)(\(\w+\))/$3/s) {
  $legalese{$key}{'list_id'} = $1;
  $legalese{$key}{'content'} = $2;
  $key++;
}

my %node = ( 1 => ''); # node structure tree
                       # initialise with single node
                       # to denote top of page
# now work on rules for tree depth
my $last_node;

# go through markers in order parsed in
for (sort {$a <=> $b;} keys %legalese) {
   # too tired to try to create rule set :)
   # but set nodes as follows
   $node{$_}{'parent'} = 'whatever parent node is'
   # either '1', $last_node, or somewhere in between
   # using %structure as your guide
   $last_node = $_;
}
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Hope that's enough pointers. By knowing what type the previous node was, you can create a valid rule for the next node by asking:

• is it of the child type expected?
• is it of the same type, incremented one?
• is it of parent type, incremented one?
• is it of grandparent type, incremented one?
• if out of structure expected, append to previous node (ie, embedded list)

cLive ;-)

That is pretty much exactly what I have so far (except that I parsed filter-style, rather than reading it all in at once). It fails to handle lists utterly however, as it sees them as sections...

By reading them all in as you have done, I could conceivably backtrack and try again if assuming it was a section led to an error, but if this is better done with a "Real" parser I don't want to reinvent the wheel. However, since I have almost no "real" parser experience, I don't know if this is an appropriate situation for one or not.

 (A)blahblahblah (i)blahblahblah
 (ii)blahblahblah