Another test program. The input string is a comma separated list of multi-digit integers. The output should be a `Dumper`ed array-ref. $VAR1 = [100,3,4]. Without the ":discard" rules I get an error about how it can only parse the first number "100" and stops at the ",".

test2.pl

use strict;
use Marpa::R2 2.038000;
use Data::Dumper;

my $grammar = Marpa::R2::Scanless::G->new(
    {   
         action_object  => 'My_Actions',
         default_action => 'do_first_arg',
         source         => \(<<'END_OF_SOURCE'),

:start       ::= Number

Number       ::= number+ separator => comma action => do_list
number       ~ [\d]+

comma        ~ [,]

# This starts to work when I enable the 2 lines below
#:discard     ~ whitespace
#whitespace   ~ [\s]+

END_OF_SOURCE
    }   
);

sub my_parser {
    my ( $grammar, $input_string ) = @_; 
    my $recce = Marpa::R2::Scanless::R->new( { grammar => $grammar } );
    my $self = bless { grammar => $grammar }, 'My_Actions';
    $self->{recce} = $recce;
    local $My_Actions::SELF = $self;
    $recce->read($input_string);
    my $value_ref = $recce->value();
    return ${$value_ref};
} ## end sub my_parser

my $value = my_parser($grammar, \"100,3,4");
print Dumper($value);

package My_Actions;
our $SELF;
sub new {return $SELF }
sub do_first_arg { shift; return shift; }
sub do_list { shift; return \@_; }