reflect.yaml

version: 1
name: Reflection (imap) test
description: |
  A world with both horizontal and vertical reflection symmetry,
  created with 'imap'.
creative: false
objectives:
  - goal:
      - Pick up four trees
    condition: |
      as base {n <- count "tree"; pure (n >= 4)}
robots:
  - name: base
    loc: [0, 0]
    dir: north
    devices:
      - logger
      - grabber
      - treads
      - branch predictor
      - scanner
      - ADT calculator
      - comparator
      - GPS receiver
      - bitcoin
solution: |
  def x = \n. \c. if (n==0) {} {c; x (n-1) c} end
  def ifC = \p. \t. \e. b <- p; if b t e end
  def findTree = ifC (ishere "tree") {whereami} {move; findTree} end
  def ell = \d. turn right; x (2*d) move; grab; pure () end
  def grabTrees = \loc. match loc \x. \y. grab; ell y; ell x; ell y end
  n <- random 10;
  x (n+1) move; turn right; move;
  loc <- findTree;
  grabTrees loc
known: [tree]
world:
  dsl: |
    let trees = if (hash % 4 == 0) then {tree, dirt} else {stone}
    in
      overlay
      [ mask (x >= 0 && y >= 0) trees
      , mask (x >= 0 && y < 0) (imap x (-y) trees)
      , mask (x < 0 && y >= 0) (imap (-x) y trees)
      , mask (x < 0 && y < 0) (imap (-x) (-y) trees)
      ]