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# ListAndAction.eyp
%{
my $num = 0;
%}

%%
S:      'c'                      
            { 
              print "S -> c\n" 
            }
    |    ('a' {$num++; print "Seen <$num> 'a's\n"; $_[1] }) S 'b'   
            { 
              print "S -> (a ) S b\n" 
            }
;
%%

# eyapp -C ListAndAction.eyp
#./ListAndAction.pm -c 'a a c b b'