perl -MB::Deparse \
     -MHTML::TableExtract \
     -le 'print B::Deparse->new->coderef2text(\&HTML::TableExtract::TableState::_taste_text)'

{
    package HTML::TableExtract::TableState;
    my($self, $text) = @_;
    my $sc = $self->_skew;
    if ($self->_terminus_trigger and $self->_column_wanted or $$self{'umbrella'}) {
        if (defined $text) {
            print STDERR "Add text '$text'\n" if $$self{'debug'} > 3;
            $self->_add_text($text, $sc);
        }
    }
    if (defined $text and $self->_any_headers and not $self->_any_htrigger) {
        $self->_htxt($text);
    }
    1;
}

##</code><code>##

$source_code =~ s/(\$self.*)$/$1

    print "skew: ".\$self->_skew."\\n"
        . "_terminus_trigger: ".\$self->_terminus_trigger."\\n"
        . "_column_wanted: ".\$self->_column_wanted."\\n"
        . "umbrella: \$\$self{'umbrella'}\\n"
        . "text: q[\$text]\\n";\n/ or die "Source patch failed";

##</code><code>##

*HTML::TableExtract::TableState::_taste_text =
    eval "sub { package Package::Name; $source_code };" or die "Eval of \$source_code failed: $@";

##</code><code>##

use B::Deparse ();

{   # Fetch the original source code
    my $source_code = B::Deparse->new->coderef2text( \&HTML::TableExtract::TableState::_taste_text );

    # Alter the source to include error trapping and the diagnostics
    $source_code = 'eval { ' . $source_code . ' }; print STDERR $@ if $@; die $@;';
    $source_code =~ s/(\$self.*)$/$1

    print "skew: ".\$self->_skew."\\n"
        . "_terminus_trigger: ".\$self->_terminus_trigger."\\n"
        . "_column_wanted: ".\$self->_column_wanted."\\n"
        . "umbrella: \$\$self{'umbrella'}\\n"
        . "text: q[\$text]\\n";\n/ or die "Source patch failed";

    # (updated - added a package declaration per 'theorbtwo')
    # Create and assign the new method into place.
    *HTML::TableExtract::TableState::_taste_test =
        eval "sub { package HTML::TableExtract::TableState; $source_code; };"
            or die "Eval of \$source_code failed: $@\n$source_code";
}