DSL EXPRESSION:
j = 2; for (i = 0; i < NR; i += 1) { $i += i }


AST:
* statement block
    * assignment "="
        * local variable "j"
        * int literal "2"
    * triple-for loop "for"
        * statement block
            * assignment "="
                * local variable "i"
                * int literal "0"
        * statement block
            * bare boolean
                * operator "<"
                    * local variable "i"
                    * context variable "NR"
        * statement block
            * assignment "="
                * local variable "i"
                * operator "+"
                    * local variable "i"
                    * int literal "1"
        * statement block
            * assignment "="
                * direct field value "i"
                * operator "+"
                    * direct field value "i"
                    * local variable "i"

a=pan,b=pan,i=1,x=0.34679014,y=0.72680286
a=eks,b=pan,i=3,x=0.75867996,y=0.52215111
a=wye,b=wye,i=6,x=0.20460331,y=0.33831853
a=eks,b=wye,i=10,x=0.38139939,y=0.13418874
