With x, x it will only go to 2 level deep. With the plus you allow to go as far as the x rule succeed and your x rule always succeed because notA always succeed due to the star without consuming anything so you fall into infinite loop.
2014-12-18 6:47 GMT+01:00 James Foster <smallt...@jgfoster.net>: > > There is something about plus that I don’t understand. In the following > code if I parse for (x , x) then I get what I expect. If I parse for (x > plus) then the image hangs. What am I doing wrong? > > James > > | a notA x y | > a := $a asParser. > notA := $a asParser negate star flatten. > x := a / notA. > y := x , x. “works fine” > y := x plus. “never finishes” > ^y end parse: 'ab’. > > > -- *Guillaume Larcheveque*
