Re: The new GEDCOM parser

Hi Rich

On 06/11/12 01:53, [email protected] wrote:
> I didn't want to clog the list with this question, unless you feel it it worth it.

Post all questions and ideas. I don't want to develop code in a vacuum. 
I only that if I /really/ know what I'm doing. Not so in this case...

> But would this new parser have reporting capabilities?

The basic module - no. It would be purely to parse the file and build a 
data structure.

Code for traversing a tree is standard, from which any imaginable output 
can be produced.

In the simplest case, any node is the root of a sub-tree, and the tree 
can be traversed and (say) printed from that point on.

What you're talking about I assume is formatting that output.

> For example, I really like the layout of the FamilyTree add-on for GRAMPS, but it looks like it is not longer being updated, and I wish it was a little more modular, that it could display more fields than it does.

I googled and found this link: 
http://www.gramps-project.org/wiki/index.php?title=Family_Tree

I have to say that's a very fancy report. Amazingly, to some extent, 
such a report is (almost) already available from a tree structure. 
Peruse the 4 links on this page to get the idea:

http://savage.net.au/Graph-module-demos.html

Hence my preference for trees.

> Plus I wish it was written in perl ; )

Don't we all.

> Rich
>
>
> ----- Original Message -----
> From: "Ron Savage"<[email protected]>
> To: [email protected]
> Sent: Monday, November 5, 2012 2:04:42 AM
> Subject: The new GEDCOM parser
>
> Hi
>
> The new GEDCOM parser
> This document is a collection of ideas which have been percolating
> in my mind for a long time.
>
> Comments welcome.
>
> Ideas
> Module name
> Genealogy::Gedcom::Parser.
>
> A place-holder, Genealogy::Gedcom
> <http://metacpan.org/release/Genealogy-Gedcom>, is already on CPAN.
>
> Note: This module was written before the new, major tools now
> available were released. See Tools below.
>
> ETA
> There is no ETA for the parser.
>
> However, certain Perl-based tools are now available which will make
> coding a simple task. See Tools below.
>
> See also 'Famous Last Words' :-).
>
> UTF-8
> The code will accept input files in utf-8, and generate files
> containing utf-8 characters.
>
> Apache and mod_perl
> These will not be required. I only mention these because references
> to them appear in the Gedcom.pm distro.
>
> Logging
> The code will have a built-in logger, so debugging, e.g., can be
> turned on with a parameter to new().
>
> This logger will use Log::Handler. See Tools below.
>
> Sub-classing
> Sub-classing the main module will be trivial, and samples will be
> provided.
>
> Sub-classing will be done with Hash::FieldHash. See Tools and the
> FAQ below.
>
> Grammars and grammar generators
> Like Gedcom.pm, the code will read a GEDCOM grammar in BNF from a file.
> I'll run this phase before shipping the module, so you don't have to.
> See Tools below, specifically Marpa::Rules::Simple.
>
> Bascially, this means the startling complexity of the code in
> Gedcom.pm is a thing of the past.
>
> Operating the parser
> Using Marpa, callbacks are triggered when input is recognized.
>
> So, when lines like these are encountered:
>
> 1 @<XREF:FAM>@ FAM
> 2 RIN<AUTOMATED_RECORD_ID>
>
> Marpa will automatically call the callback attached to each tag.
>
> Callbacks will probably have names like 'do_fam' and 'do_rin', i.e.
> of the format 'do_$tag'.
>
> The parameters passed to the callback include the non-tag text on
> the line.
>
> Default callbacks for all tags will be provided, each one doing its
> part in parsing the parameters to the tag, and storing the result.
>
> The result will probably be stored in a tree. See Tools below,
> specifically Tree::DAG_Node.
>
> Database support
> A DBD::SQLite database is possible.
>
> Tools
> o Hash::FieldHash
> Simplifies class-building.
>
> As for the obvious question, why not use Moose, see the FAQ below.
>
> o Log::Handling
> Simplifies logging.
>
> o Marpa::R2
> This is the modern way to do parsing.
>
> Home page<http://jeffreykegler.github.com/Marpa-web-site/>.
>
> Jeffrey's blog about Marpa
> <http://jeffreykegler.github.com/Ocean-of-Awareness-blog/>.
>
> My recent article about lexing and parsing with Marpa
>
> <http://www.perl.com/pub/2012/10/an-overview-of-lexing-and-parsing.html>.
>
> o MarpaX::Simple::Rules
> This module reads a grammar in BNF and generates a Marpa grammar.
>
> Hence it will read a BNF version of the GEDCOM spec and output
> the matching Marpa grammar.
>
> o Tree::DAG_Node
> The most sophisticated tree-handling code on CPAN. I've recently
> become co-maintainer of this module.
>
> FAQ
> Why did you choose Hash::FieldHash over Moose?
> My policy is to use the light-weight Hash::FieldHash for stand-alone
> modules and Moose for applications.
>
> Why did you choose to store the data in a tree?
> A GEDCOM file's structure can be viewed as a tree, so my initial
> plan is to store the data likewise.
>
>


-- 
Ron Savage
http://savage.net.au/
Ph: 0421 920 622