ROOT (token: short_text [lag_newlines/spaces] {pos_id})
 ¦--COMMENT: # = r [0/0] {1}                           
 ¦--expr_or_assign_or_help: a = 3 [1/0] {2}            
 ¦   ¦--expr: a [0/1] {4}                              
 ¦   ¦   °--SYMBOL: a [0/0] {3}                        
 ¦   ¦--EQ_ASSIGN: = [0/1] {5}                         
 ¦   °--expr: 3 [0/0] {7}                              
 ¦       °--NUM_CONST: 3 [0/0] {6}                     
 ¦--expr: data_ [1/0] {8}                              
 ¦   ¦--expr: data_ [0/0] {10}                         
 ¦   ¦   °--SYMBOL_FUNCTION_CALL: data_ [0/0] {9}      
 ¦   ¦--'(': ( [0/0] {11}                              
 ¦   ¦--SYMBOL_SUB: a [0/1] {12}                       
 ¦   ¦--EQ_SUB: = [0/1] {13}                           
 ¦   ¦--expr: 3 [0/0] {15}                             
 ¦   ¦   °--NUM_CONST: 3 [0/0] {14}                    
 ¦   °--')': ) [0/0] {16}                              
 ¦--COMMENT: # sem [2/0] {17}                          
 ¦--expr: a [1/0] {19}                                 
 ¦   °--SYMBOL: a [0/0] {18}                           
 ¦--';': ; [0/1] {20}                                  
 ¦--expr: b [0/1] {22}                                 
 ¦   °--SYMBOL: b [0/0] {21}                           
 ¦--';': ; [0/0] {23}                                  
 ¦--expr: c [0/0] {25}                                 
 ¦   °--SYMBOL: c [0/0] {24}                           
 ¦--';': ; [0/0] {26}                                  
 ¦--expr: d [0/0] {28}                                 
 ¦   °--SYMBOL: d [0/0] {27}                           
 ¦--COMMENT: # quo [3/0] {29}                          
 ¦--expr: "text [1/0] {31}                             
 ¦   °--STR_CONST: "text [0/0] {30}                    
 ¦--expr: 'text [1/0] {33}                             
 ¦   °--STR_CONST: 'text [0/0] {32}                    
 ¦--COMMENT: # add [4/0] {34}                          
 ¦--expr: a %>% [1/0] {35}                             
 ¦   ¦--expr: a [0/1] {38}                             
 ¦   ¦   °--SYMBOL: a [0/0] {37}                       
 ¦   ¦--SPECIAL-PIPE: %>% [0/2] {39}                   
 ¦   ¦--expr: b [1/1] {41}                             
 ¦   ¦   °--SYMBOL: b [0/0] {40}                       
 ¦   ¦--SPECIAL-PIPE: %>% [0/2] {42}                   
 ¦   °--expr: c [1/0] {44}                             
 ¦       °--SYMBOL: c [0/0] {43}                       
 ¦--COMMENT: # add [2/0] {45}                          
 °--expr: a %>% [1/0] {46}                             
     ¦--expr: a [0/1] {49}                             
     ¦   °--SYMBOL: a [0/0] {48}                       
     ¦--SPECIAL-PIPE: %>% [0/1] {50}                   
     ¦--expr: b [0/1] {52}                             
     ¦   °--SYMBOL: b [0/0] {51}                       
     ¦--SPECIAL-PIPE: %>% [0/2] {53}                   
     °--expr: c [1/0] {55}                             
         °--SYMBOL: c [0/0] {54}                       
