version: 1
name: Density test
creative: true
description: Count entities in an area
objectives:
  - goal:
      - Pick up 3 entities.
    condition: |
      j <- robotnamed "judge";
      as j {
        c <- density ((0, 0), (3, 3));
        return $ c <= 13;
      };
solution: |
  def doN = \n. \f. if (n > 0) {f; doN (n - 1) f} {}; end;
  doN 3 (move; grab);
robots:
  - name: base
    dir: [1, 0]
    display:
      char: Ω
      attr: robot
    devices:
      - logger
      - string
      - grabber
      - compass
      - treads
      - ADT calculator
  - name: judge
    dir: [1, 0]
    system: true
    display:
      invisible: false
      char: J
known: []
world:
  dsl: |
    {blank, boulder}
  palette:
    'Ω': [grass, tree, base]
    'J': [grass, tree, judge]
    '.': [grass, tree]
    '*': [grass, flower]
  upperleft: [76, -89]
  map: |
   *.*.
   Ω*.*
   *.*.
   J*.*