I've been using Opcode and Opcodes to grok B and the opcodes. For example, 
#!/usr/bin/perl 

use strict;
use Opcodes;
use Opcode qw(opdump);
use Data::Dumper::Concise;

print Dumper
  (opdump),             "\n",
  (scalar opcodes),     "\n",
  (opname2code('gv')),  "\n",
  (opdesc(7)),          "\n",
  (opclass(7)),         "\n",
  (opdesc(opclass(7))), "\n";

(opdump) lists all the opcodes.
(scalar opcodes) the number of opcodes for your version of perl
(opname2code('gv')) gives the number('code') of gv.
(opdesc(7)) the number for gv. Gives a short description
(opclass(7)) - classes such as OP, COP, UNOP, BINOP, etc.
             - here, gv is a svop_or_padop which is 6
(opdesc(opclass(7))) - tells you that it's a scalar variable

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In reply to Re: Where to find info on low level perl internals names? by Khen1950fx
in thread Where to find info on low level perl internals names? by Anonymous Monk

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