ROOT (token: short_text [lag_newlines/spaces] {pos_id})
 ¦--COMMENT: # a c [0/0] {1}                           
 °--expr:  [1/0] {2}                                   
     ¦--expr:  [0/1] {4}                               
     ¦   °--SYMBOL: a [0/0] {3}                        
     ¦--LEFT_ASSIGN: <- [0/1] {5}                      
     °--expr:  [0/0] {6}                               
         ¦--FUNCTION: funct [0/0] {7}                  
         ¦--'(': ( [0/0] {8}                           
         ¦--SYMBOL_FORMALS: x [0/0] {9}                
         ¦--')': ) [0/1] {10}                          
         °--expr:  [0/0] {11}                          
             ¦--'{': { [0/2] {12}                      
             ¦--expr:  [1/0] {14}                      
             ¦   °--SYMBOL: x [0/0] {13}               
             °--'}': } [1/0] {15}                      
