Bug #119932 for Filter-Simple: even with a null filter F::S mangles line numbers in code with HEREDOCs

(dumping my observations from source-diving) The mangling of line numbers is due to the indiscriminate use of Text::Balanced::extract_quotelike resp. the reassembly of multiline here document strings in &gen_std_filter_for() . The reassembly doesn't discriminate between inline-use and newline use: my $decl = <<'XS'; foo XS my $decl2 = <<'XS' bar XS ; The likely change is in s/$extractor/${$components[unpack('N',$1)]}/g; which needs to know whether the here-document was "inline" or at the end of a line. This needs to have been remembered in the (implicit) invocations of \&extract_quotelike. The approach I'm currently playing with is a wrapper around extract_quotelike, which stores the information about whether information follows on the same line of the here document declaration ("inline" case) in the class name by blessing into DONT_MATCH_INLINE instead of DONT_MATCH. The case is not completely trivial due to Perl allowing interesting combinations of quoting across multiple lines, for example: my @decl4 = (<<'XS', q{); nananana XS batman }); ... which stores the strings "nananana\n" and "batman\n" in @decl4.