DSL EXPRESSION:
$new = ${a} . ${b}


AST:
* statement block
    * assignment "="
        * direct field value "new"
        * dot operator "."
            * direct field value "a"
            * direct field value "b"

a   b   i x                   y                   new
pan pan 1 0.3467901443380824  0.7268028627434533  panpan
eks pan 2 0.7586799647899636  0.5221511083334797  ekspan
wye wye 3 0.20460330576630303 0.33831852551664776 wyewye
eks wye 4 0.38139939387114097 0.13418874328430463 ekswye
