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B::Graph, version 0.51

Copyright (C) 1997, 1998, 2000 Stephen McCamant. All rights reserved.
This program is free software; you can redistribute and/or modify
it under the same terms as Perl itself.

Module list information:
B::Graph	bdpr	Perl Compiler backend to diagram OP trees

This module is a layer between the perl-internals-examining parts of
Malcolm Beattie's perl compiler (the B::* classes) and your favorite
graph layout tool (currently Dot and VGC are supported, but adding
others would be easy). It examines the internal structures that perl
builds to represent your code (OPs and SVs), and generates
specifications for multicolored boxes and arrows to represent them.

New in this version:
 - Turned off fileGVs in versions that don't have them
 - Minor doc cleanups
 - Changed my email address

This version should work with perl 5.6.0.

Other things you need:

* perl 5.005 or later

(Earlier versions of perl will work to various extents with old alpha
versions of the compiler, but the version in 5.005 has several fixes,
so it is recommended.)

* Visualization of Compiler Graphs (`the VGC tool')
http://www.cs.uni-sb.de/RW/users/sander/html/gsvcg1.htm
     OR
The graph visualization package from from AT&T (contains Dot)
http://www.research.att.com/sw/tools/graphviz/
(VCG has Windows and X11 interfaces, and is good for interactive
viewing; Dot is a batch program that generates good PostScript, so
you'll need either a printer or an previewer)

* A basic understanding of how perl's internals work (see perlguts(1))
     OR
A willingness to stare at complicated-looking diagrams, most of which
you don't understand
(Seriously, this module can be a good tool for learning about how perl
works inside -- for instance, its output is a lot more intutive that
`perl -Dx''s, IMHO)

BUILDING

Just like any other module:
% perl Makefile.PL
% make
% make install

(`make test' currently doesn't do anything interesting. Also, with
5.005 it may fail to find the `Perl_byterun' symbol, but B::Graph will
still run fine. If you just want to test whether B::Graph works on
your platform (hello CPAN testers!), just run one of the examples
below and check that the output doesn't look like an error message.)

EXAMPLE

(Add `-Mblib' if you haven't done `make install')

% perl -MO=Graph,-vcg -e '$a = $b + $c' >graph.vcg
% xvcg graph.vcg
    OR
% perl -MO=Graph,-dot -e '$a = $b + $c' | dot -Tps >graph.ps
% gv graph.ps (or your favorite PostScript previewer)

(depending on your shell, you might be able to do everyting in one
line -- in zsh, say 
% xvcg =(perl -MO=Graph,-vcg -e '...')
)

You may notice that this is the same example used in perlguts (the
section titled `code tree'). A comparison to the ASCII art there will
give you an idea of what `slightly more complicated' means.

For more detailed information, see the POD at the end of Graph.pm.


Send questions, bug reports, and feature requests to me, Stephen
McCamant <[email protected]>.