ROOT (token: short_text [lag_newlines/spaces] {pos_id})
 °--expr:  [0/0] {1}                                   
     ¦--expr:  [0/1] {4}                               
     ¦   °--NUM_CONST: 1 [0/0] {3}                     
     ¦--'+': + [0/13] {5}                              
     ¦--expr:  [1/1] {7}                               
     ¦   °--NUM_CONST: 2 [0/0] {6}                     
     ¦--'+': + [0/1] {8}                               
     °--expr:  [0/0] {9}                               
         ¦--'(': ( [0/0] {10}                          
         ¦--expr:  [1/0] {11}                          
         ¦   ¦--expr:  [0/1] {13}                      
         ¦   ¦   °--NUM_CONST: 3 [0/0] {12}            
         ¦   ¦--'+': + [0/1] {14}                      
         ¦   °--expr:  [0/0] {16}                      
         ¦       °--NUM_CONST: 4 [0/0] {15}            
         °--')': ) [0/0] {17}                          
