ROOT (token: short_text [lag_newlines/spaces] {pos_id})
 °--expr: if(TR [0/0] {1}                              
     ¦--IF: if [0/0] {2}                               
     ¦--'(': ( [0/0] {3}                               
     ¦--expr: TRUE [0/0] {5}                           
     ¦   °--NUM_CONST: TRUE [0/0] {4}                  
     ¦--')': ) [0/1] {6}                               
     ¦--expr: x [0/1] {8}                              
     ¦   °--SYMBOL: x [0/0] {7}                        
     ¦--ELSE: else [0/1] {9}                           
     °--expr: y [0/0] {11}                             
         °--SYMBOL: y [0/0] {10}                       
