B/Utils version 0.01
====================

NAME
    B::Utils - Helper functions for op tree manipulation

SYNOPSIS
      use B::Utils;

FUNCTIONS
    "all_starts"
    "all_roots"
       Returns a hash of all of the starting ops or root ops of optrees,
       keyed to subroutine name; the optree for main program is simply keyed
       to "main".

       Note: Certain "dangerous" stashes are not scanned for subroutines:
       the list of such stashes can be found in "@B::Utils::bad_stashes".
       Feel free to examine and/or modify this to suit your needs. The
       intention is that a simple program which uses no modules other than
       "B" and "B::Utils" would show no addition symbols.

       This does not return the details of ops in anonymous subroutines
       compiled at compile time. For instance, given

           $a = sub { ... };

       the subroutine will not appear in the hash. This is just as well,
       since they're anonymous... If you want to get at them, use...

    "anon_subs()"
       This returns an array of hash references. Each element has the keys
       "start" and "root". These are the starting and root ops of all of the
       anonymous subroutines in the program.

    "$op->oldname"
       Returns the name of the op, even if it is currently optimized to
       null. This helps you understand the stucture of the op tree.

    "$op->kids"
       Returns an array of all this op's non-null children.

    "$op->parent"
       Returns the parent node in the op tree, if possible. Currently
       "possible" means "if the tree has already been optimized"; that is,
       if we're during a "CHECK" block. (and hence, if we have valid "next"
       pointers.)

       In the future, it may be possible to search for the parent before we
       have the "next" pointers in place, but it'll take me a while to
       figure out how to do that.

    "$op->previous"
       Like "$op->next", but not quite.

AUTHOR
       Simon Cozens, "simon@cpan.org"

TODO
       I need to add more Fun Things, and possibly clean up some parts where
       the (previous/parent) algorithm has catastrophic cases, but it's more
       important to get this out right now than get it right.

INSTALLATION

To install this module type the following:

   perl Makefile.PL
   make
   make test
   make install

DEPENDENCIES

This module does *not* require anything that's not in core.

COPYRIGHT AND LICENCE

AL & GPL. You know the score.

Copyright (C) 2001 Simon Cozens