Thank you so much guys, I learned some things that were confusing me and turns out that it is ok to just use Parse::RecDescent without BNF. This really helps. I have just one question. As I must use Parse::RecDescent and not Marpa, I need to parse Abstract syntax tree and copy data from dumper to array and then export it to JSON format. The code is this:

use Parse::RecDescent;
use Data::Dumper;

$::RD_AUTOACTION = q { [ @item ] };


$grammar = q{
start: seq

seq: '(' seqstr(s) ')'

seqstr: seq | tagstr

tagstr: OZN ( seq | rijec )

OZN: /[A-Z.,?'*:`*]+ /
rijec: /[\w-?,:<*`*]+/
};

my $parser=Parse::RecDescent->new($grammar);
my $result = $parser->start("(SBARQ (WHADVP (WRB Where))(SQ (VBZ is)(N
+P (NNP Inoco))(VP (VBN based)))(. ?))");
print Dumper($result);

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In reply to Re^2: converting context free grammar to BNF by nido203
in thread converting context free grammar to BNF by nido203

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