DSL EXPRESSION:
$i /= 2


AST:
* statement block
    * assignment "="
        * direct field value "i"
        * operator "/"
            * direct field value "i"
            * int literal "2"

a   b   i   x                   y
pan pan 0.5 0.3467901443380824  0.7268028627434533
eks pan 1   0.7586799647899636  0.5221511083334797
wye wye 1.5 0.20460330576630303 0.33831852551664776
eks wye 2   0.38139939387114097 0.13418874328430463
