1package B::Terse; 2 3our $VERSION = '1.09'; 4 5use strict; 6use B qw(class @specialsv_name); 7use B::Concise qw(concise_subref set_style_standard); 8use Carp; 9 10sub terse { 11 my ($order, $subref) = @_; 12 set_style_standard("terse"); 13 if ($order eq "exec") { 14 concise_subref('exec', $subref); 15 } else { 16 concise_subref('basic', $subref); 17 } 18} 19 20sub compile { 21 my @args = @_; 22 my $order = @args ? shift(@args) : ""; 23 $order = "-exec" if $order eq "exec"; 24 unshift @args, $order if $order ne ""; 25 B::Concise::compile("-terse", @args); 26} 27 28sub indent { 29 my ($level) = @_ ? shift : 0; 30 return " " x $level; 31} 32 33 34sub B::SV::terse { 35 my($sv, $level) = (@_, 0); 36 my %info; 37 B::Concise::concise_sv($sv, \%info); 38 my $s = indent($level) 39 . B::Concise::fmt_line(\%info, $sv, 40 "#svclass~(?((#svaddr))?)~#svval", 0); 41 chomp $s; 42 print "$s\n" unless defined wantarray; 43 $s; 44} 45 46sub B::NULL::terse { 47 my ($sv, $level) = (@_, 0); 48 my $s = indent($level) . sprintf "%s (0x%lx)", class($sv), $$sv; 49 print "$s\n" unless defined wantarray; 50 $s; 51} 52 53sub B::SPECIAL::terse { 54 my ($sv, $level) = (@_, 0); 55 my $s = indent($level) 56 . sprintf( "%s #%d %s", class($sv), $$sv, $specialsv_name[$$sv]); 57 print "$s\n" unless defined wantarray; 58 $s; 59} 60 611; 62 63__END__ 64 65=head1 NAME 66 67B::Terse - Walk Perl syntax tree, printing terse info about ops 68 69=head1 SYNOPSIS 70 71 perl -MO=Terse[,OPTIONS] foo.pl 72 73=head1 DESCRIPTION 74 75This module prints the contents of the parse tree, but without as much 76information as CPAN module B::Debug. For comparison, C<print "Hello, world."> 77produced 96 lines of output from B::Debug, but only 6 from B::Terse. 78 79This module is useful for people who are writing their own back end, 80or who are learning about the Perl internals. It's not useful to the 81average programmer. 82 83This version of B::Terse is really just a wrapper that calls L<B::Concise> 84with the B<-terse> option. It is provided for compatibility with old scripts 85(and habits) but using B::Concise directly is now recommended instead. 86 87For compatibility with the old B::Terse, this module also adds a 88method named C<terse> to B::OP and B::SV objects. The B::SV method is 89largely compatible with the old one, though authors of new software 90might be advised to choose a more user-friendly output format. The 91B::OP C<terse> method, however, doesn't work well. Since B::Terse was 92first written, much more information in OPs has migrated to the 93scratchpad datastructure, but the C<terse> interface doesn't have any 94way of getting to the correct pad. As a kludge, the new version will 95always use the pad for the main program, but for OPs in subroutines 96this will give the wrong answer or crash. 97 98=head1 AUTHOR 99 100The original version of B::Terse was written by Malcolm Beattie, 101E<lt>mbeattie@sable.ox.ac.ukE<gt>. This wrapper was written by Stephen 102McCamant, E<lt>smcc@MIT.EDUE<gt>. 103 104=cut 105