in function

[btedji]

I cant get any 'in' functions to work

How could I get something like this to work:

if (players[0].x in |x,x+1|=true) {command}

or something like that

[grim_squeaker_x]

By removing the =true part ;)
Plus you'll have to put it in a timeout loop. Otherwise Graal won't keep checking for it.