ROOT (token: short_text [lag_newlines/spaces] {id})
 ¦--expr: a <-  [0/0] {12}                         
 ¦   ¦--expr: a [0/1] {3}                          
 ¦   ¦   °--SYMBOL: a [0/0] {1}                    
 ¦   ¦--LEFT_ASSIGN: <- [0/1] {2}                  
 ¦   °--expr: {3} [0/0] {10}                       
 ¦       ¦--'{': { [0/0] {4}                       
 ¦       ¦--expr: 3 [0/0] {6}                      
 ¦       ¦   °--NUM_CONST: 3 [0/0] {5}             
 ¦       °--'}': } [0/0] {7}                       
 °--expr: a <-  [2/0] {45}                         
     ¦--expr: a [0/1] {19}                         
     ¦   °--SYMBOL: a [0/0] {17}                   
     ¦--LEFT_ASSIGN: <- [0/1] {18}                 
     °--expr: {


  [0/0] {43}                  
         ¦--'{': { [0/2] {20}                      
         ¦--expr: 3+1 [3/0] {30}                   
         ¦   ¦--expr: 3 [0/0] {25}                 
         ¦   ¦   °--NUM_CONST: 3 [0/0] {24}        
         ¦   ¦--'+': + [0/0] {26}                  
         ¦   °--expr: 1 [0/0] {28}                 
         ¦       °--NUM_CONST: 1 [0/0] {27}        
         °--'}': } [5/0] {41}                      
