[![Build Status](https://travis-ci.org/rocky/p5-B-DeparseTree.png)](https://travis-ci.org/rocky/p5-B-DeparseTree) Synopsis -------- Perl's B::Deparse but we save abstract tree information and associate that with Perl text fragments. These are fragments accessible by OP address. With this, you can determine get exactly where you inside Perl in a program with granularity finer that at a line number boundary. Uses for this could be in stack trace routines like _Carp_. It is used in the [deparse](https://metacpan.org/pod/Devel::Trepan::Deparse) command extension to [Devel::Trepan](https://metacpan.org/pod/Devel::Trepan). Example ------- use B::DeparseTree; my $deparse = B::DeparseTree->new(); # create a subroutine to deparse... sub my_abs($) { return $a < 0 ? -$a : $a; }; my $deparse_tree = B::DeparseTree->new(); my $tree_node = $deparse_tree->coderef2info(\&my_abs); print $tree_node->{text}; The above produces: ($) { return $a < 0 ? -$a : $a } but the result are reconstructed purely from the OPnode tree. To show parent-child information in the tree: use B::DeparseTree::Fragment; B::DeparseTree::Fragment::dump_relations($deparse_tree); which produces: 0: ================================================== Child info: addr: 0xe87280, parent: 0x16684c0 op: pushmark text: return $a < 0 ? -$a : $a ($)... return $a < 0 ? -$a : $a ~~~~~~ 0: ================================================== 1: ================================================== Child info: addr: 0xe8b550, parent: 0xe9cba0 op: gvsv text: $a return $a < 0 ? -$a : $a -- 1: ================================================== 2: ================================================== Child info: addr: 0xe8cd20, parent: 0xe9cba0 op: gvsv text: $a return $a < 0 ? -$a : $a -- 2: ================================================== 3: ================================================== Child info: addr: 0xe966e0, parent: 0xe9cba0 op: B::IV=SCALAR(0x18e5b98) text: 0 return $a < 0 ? -$a : $a - 3: ================================================== 4: ================================================== Child info: addr: 0xe9cba0, parent: 0x1668650 op: lt text: $a < 0 return $a < 0 ? -$a : $a ------ 4: ================================================== 5: ================================================== Child info: addr: 0xf2b520, parent: 0x1668650 op: negate text: -$a return $a < 0 ? -$a : $a --- 5: ================================================== 6: ================================================== Child info: addr: 0x1327200, parent: 0x1667c60 op: nextstate text: 6: ================================================== 7: ================================================== Child info: addr: 0x161a4f0, parent: 0xf2b520 op: gvsv text: $a return $a < 0 ? -$a : $a -- 7: ================================================== .... Installation ------------ Currently we support Perl 5.14, 5.16, 5.18, 5.20, 5.22, 5.24, 5.26, and 5.28. To install this Devel::Trepan, run the following commands: perl Build.PL make make test [sudo] make install License and Copyright --------------------- Copyright (C) 2015, 2017, 2018 Rocky Bernstein See also -------- * [Exact Perl location with B::Deparse (and Devel::Callsite)](http://blogs.perl.org/users/rockyb/2015/11/exact-perl-location-with-bdeparse-and-develcallsite.html) * [Rewriting B:Deparse and Reintroducing B::DeparseTree and (part 1)](http://blogs.perl.org/users/rockyb/2018/06/introducing-bdeparsetree-and-rewriting-bdeparse-part-1.html)