refactor and start shifting to FixedSeq (currently broken)

colors.nim

@@ -1,139 +0,0 @@
-import strutils
-
-
-type
-  Color* = enum
-    cRed, cGreen, cBlue, cYellow, cPurple
-
-  ColorStack* = object
-    pieces: array[5, int8]
-    last: int8
-
-
-proc init*(s: var ColorStack) =
-  for i in 0..4:
-    s.pieces[i] = -1
-  s.last = -1
-
-
-proc `[]`*(s: ColorStack, i: Natural): Color =
-  if i > s.last:
-    raise newException(IndexDefect, "index " & $i & " is out of bounds.")
-  result = Color(s.pieces[i])
-
-
-proc `[]`*(s: ColorStack, i: BackwardsIndex): Color =
-  if s.last == -1:
-    raise newException(IndexDefect, "index out of bounds, the container is empty.") # matching stdlib again
-  result = Color(s.pieces[s.last - int8(i) + 1])
-
-
-proc `[]=`*(s: var ColorStack, i: Natural, v: Color) =
-  if i > s.last:
-    raise newException(IndexDefect, "index " & $i & " is out of bounds.")
-  s.pieces[i] = int8(v)
-
-
-proc `$`*(s: ColorStack): string =
-  result.add("St@[")
-  for i in 0 .. s.last:
-    let c = Color(s.pieces[i])
-    result.add($c)
-    if i < s.last:
-      result.add(", ")
-  result.add("]")
-
-
-proc high*(s: ColorStack): int8 =
-  result = s.last
-
-
-proc low*(s: ColorStack): int8 =
-  result = case s.last
-  of -1: 0 # a bit weird but it's how the stdlib seq works
-  else: s.last
-
-
-proc len*(s: ColorStack): int8 =
-  result = s.last + 1
-
-
-iterator items*(s: ColorStack): Color =
-  for i in 0 .. s.last:
-    yield Color(s.pieces[i])
-
-
-iterator asInt*(s: ColorStack): int8 =
-  for i in 0 .. s.last:
-    yield s.pieces[i] # no conversion, should speed up hashing? maybe
-
-
-iterator pairs*(s: ColorStack): auto =
-  var count = 0
-  for c in s:
-    yield (count, c)
-    inc count
-
-
-proc add*(s: var ColorStack, c: Color) =
-  let i = s.last + 1
-  s.pieces[i] = int8(c) # will raise exception if out of bounds
-  s.last = i
-
-
-proc insert*(s: var ColorStack, c: Color, idx: Natural = 0) =
-  for i in countdown(s.last, int8(idx)):
-    swap(s.pieces[i], s.pieces[i + 1]) # will also raise exception if out of bounds
-  s.pieces[idx] = int8(c)
-  inc s.last
-
-
-proc delete*(s: var ColorStack, idx: Natural) =
-  if idx > s.last:
-    raise newException(IndexDefect, "index " & $idx & " is out of bounds.")
-  s.pieces[idx] = -1
-  dec s.last
-  for i in int8(idx) .. s.last:
-    swap(s.pieces[i], s.pieces[i + 1])
-
-
-proc find(s: ColorStack, c: Color): int8 =
-  let needle = int(c)
-  for i, v in s.pieces:
-    if v == needle:
-      return i
-  return -1
-
-
-proc moveSubstack*(src, dst: var ColorStack; start: Natural) =
-  var count = 0 # have to track this separately apparently
-  for idx in (int8(start) .. src.last):
-    swap(src.pieces[idx], dst.pieces[dst.last + 1 + count])
-    inc count
-  dst.last += int8(count)
-  src.last -= int8(count)
-
-
-proc moveSubstackPre*(src, dst: var ColorStack; start: Natural) =
-  let ssLen = src.last - start + 1 # length of substack
-  for i in countdown(dst.last, 0):
-    swap(dst.pieces[i], dst.pieces[i + ssLen])
-
-  var count = 0
-  for i in start .. src.last:
-    swap(src.pieces[i], dst.pieces[count])
-    inc count
-
-  dst.last += int8(ssLen)
-  src.last -= int8(ssLen)
-
-
-proc display(s: ColorStack) =
-  var p: seq[string]
-  for i in s.pieces:
-    if i == -1:
-      p.add("none")
-    else:
-      p.add($Color(i))
-  echo "pieces: @[", p.join(", "), "], last: ", s.last
-  echo "len: ", s.len, "\n"

combinators.nim

@@ -1,7 +1,8 @@
-import algorithm, sequtils
+import sequtils
+import fixedseq, game
 
 
-iterator allPermutations*[T](x: seq[T]): seq[T] =
+iterator allPermutations*(x: FixedSeq): FixedSeq =
   # returns all permutations of a given seq. Order is wonky but we don't care.
   var workingCopy = x
   yield workingCopy
@@ -12,12 +13,12 @@ iterator allPermutations*[T](x: seq[T]): seq[T] =
     yield workingCopy
 
 
-iterator allDigits*(lo, hi, size: Natural): seq[int] =
+iterator allDigits*(lo, hi, size: Natural): auto =
   if size > 0: # otherwise we get an infinite loop
-    # we use uninitialized since we will initialize it below, but not necessarily with 0s
+    var digits: FixedSeq[5, int8, int8]
-    var digits = newSeqUninitialized[int](size)
+    digits.initFixedSeq
-    for i in 0 .. digits.high:
+    for i in 0 ..< size:
-      digits[i] = lo
+      digits.add(lo)
 
     var complete = false
     while not complete:
@@ -32,9 +33,12 @@ iterator allDigits*(lo, hi, size: Natural): seq[int] =
           digits[i] = lo
 
 
-iterator possibleFutures*[C](dice: seq[C]): seq[tuple[color: C, value: int]] =
+iterator possibleFutures*(dice: FixedSeq): auto =
   # iterate over all possible sequences of die rolls. Each outcome
   # is returned as a 5-sequence of (color, number) tuples.
   for perm in dice.allPermutations:
-    for d in allDigits(1, 3, dice.len):
+    for digits in allDigits(1, 3, dice.len):
-      yield zip(perm, d)
+      var f = initFixedSeq(5, Die, int8)
+      for i in 0 .. dice.high:
+        f.add((perm[i], digits[i]))
+      yield f

fixedseq.nim

@@ -0,0 +1,135 @@
+import algorithm
+
+
+type
+  FixedSeq*[Idx: static int; Contents; Pointer: SomeSignedInt] = object
+    data: array[Idx, Contents]
+    last: Pointer
+
+
+proc initFixedSeq*(size: static Natural; cType: typedesc; pType: typedesc[SomeSignedInt]): auto =
+  var s: FixedSeq[size, cType, pType]
+  s.last = -1
+  result = s
+
+proc initFixedSeq*(s: var FixedSeq) =
+  s.last = -1
+
+
+proc `[]`*(s: var FixedSeq, i: Natural): var FixedSeq.Contents =
+  if i > s.last:
+    raise newException(IndexDefect, "index " & $i & " is out of bounds.")
+  s.data[i]
+
+
+proc `[]`*(s: FixedSeq, i: BackwardsIndex): auto =
+  if s.last == -1:
+    raise newException(IndexDefect, "index out of bounds, the container is empty.") # matching stdlib again
+  s.data[s.last - typeof(s.last)(i) + 1]
+
+
+proc `[]=`*(s: var FixedSeq, i: Natural, v: FixedSeq.Contents) =
+  if i > s.last:
+    raise newException(IndexDefect, "index " & $i & " is out of bounds.")
+  s.data[i] = v
+
+
+proc high*(s: FixedSeq): auto =
+  result = s.last
+
+
+proc low*(s: FixedSeq): auto =
+  result = case s.last
+  of -1: 0 # a bit weird but it's how the stdlib seq works
+  else: s.last
+
+
+proc len*(s: FixedSeq): auto =
+  result = s.last + 1
+
+
+iterator items*(s: FixedSeq): auto =
+  for i in 0 .. s.last:
+    yield s.data[i]
+
+
+iterator asInt*(s: FixedSeq): int8 =
+  for i in 0 .. s.last:
+    yield int8(s.data[i]) # now we do have to convert
+
+
+iterator pairs*(s: FixedSeq): auto =
+  var count = 0
+  for c in s:
+    yield (count, c)
+    inc count
+
+
+proc add*(s: var FixedSeq, v: FixedSeq.Contents) =
+  let i = s.last + 1
+  s.data[i] = v # will raise exception if out of bounds
+  s.last = i
+
+
+proc insert*(s: var FixedSeq, v: FixedSeq.Contents, idx: Natural = 0) =
+  for i in countdown(s.last, typeof(s.last)(idx)):
+    swap(s.data[i], s.data[i + 1]) # will also raise exception if out of bounds
+  s.data[idx] = v
+  inc s.last
+
+
+proc delete*(s: var FixedSeq, idx: Natural) =
+  if idx > s.last:
+    raise newException(IndexDefect, "index " & $idx & " is out of bounds.")
+  s.data[idx] = -1
+  dec s.last
+  for i in typeof(s.last)(idx) .. s.last:
+    swap(s.data[i], s.data[i + 1])
+
+
+proc find*(s: FixedSeq, needle: FixedSeq.Contents): FixedSeq.Pointer =
+  for i, v in s.data:
+    if v == needle:
+      return i
+  return -1
+
+
+proc nextPermutation*(s: var FixedSeq): bool = s.data.nextPermutation
+
+proc prevPermutation*(s: var FixedSeq): bool = s.data.prevPermutation
+
+proc maxSize*(s: FixedSeq): FixedSeq.Pointer = s.data.len
+
+
+proc moveSubstack*(src, dst: var FixedSeq; start: Natural) =
+  var count: typeof(src.last) = 0 # have to track this separately apparently
+  for idx in start .. src.last:
+    swap(src.data[idx], dst.data[dst.last + 1 + count])
+    inc count
+  dst.last += count
+  src.last -= count
+
+
+proc moveSubstackPre*(src, dst: var FixedSeq; start: Natural) =
+  let ssLen = typeof(src.last)(src.last - start + 1) # length of substack
+  for i in countdown(dst.last, 0):
+    swap(dst.data[i], dst.data[i + ssLen])
+
+  var count = 0
+  for i in start .. src.last:
+    swap(src.data[i], dst.data[count])
+    inc count
+
+  dst.last += ssLen
+  src.last -= ssLen
+
+
+# proc display(s: ColorStack) =
+#   var p: seq[string]
+#   for i in s.pieces:
+#     if i == -1:
+#       p.add("none")
+#     else:
+#       p.add($Color(i))
+#   echo "pieces: @[", p.join(", "), "], last: ", s.last
+#   echo "len: ", s.len, "\n"

game.nim

@@ -0,0 +1,133 @@
+import hashes, options
+import fixedseq
+
+
+type
+  Color* = enum
+    cRed, cGreen, cBlue, cYellow, cPurple
+
+  ColorStack* = FixedSeq[5, Color, int8]
+
+
+proc `$`*(s: ColorStack): string =
+  result.add("St@[")
+  for i, color in s:
+    result.add($color)
+    if i < s.high:
+      result.add(", ")
+  result.add("]")
+
+
+type
+  Die* = tuple[color: Color, value: int]
+
+  Tile* = enum
+    tBackward = -1,
+    tForward = 1
+
+  Square* = object
+    camels: ColorStack
+    tile: Option[Tile]
+
+  Board* = object
+    squares*: array[1..16, Square]
+    camels*: array[Color, range[1..16]]
+    diceRolled*: array[Color, bool]
+    leader*: Option[Color]
+    gameOver*: bool
+    initialized: bool
+
+
+const allDice = @[cRed, cGreen, cBlue, cYellow, cPurple]
+
+
+proc `[]`*[T](b: var Board, idx: T): var Square =
+  b.squares[idx]
+
+
+proc hash*(b: Board): Hash =
+  var h: Hash = 0
+  # there could be a tile anywhere so we have to check all squares
+  for i, sq in b.squares:
+    if sq.camels.len > 0 or sq.tile.isSome:
+      h = h !& i
+      if sq.tile.isSome:
+        h = h !& int(sq.tile.get) * 10 # so it isn't confused with a camel
+      else:
+        for c in sq.camels.asInt:
+          h = h !& c
+  result = !$h
+
+
+proc init*(b: var Board) =
+  for sq in b.squares.mitems:
+    sq.camels.initFixedSeq
+  b.initialized = true
+
+
+proc display*(b: Board, start, stop: int) =
+  for i in start..stop:
+    let sq = b.squares[i]
+    let lead = $i & ": "
+    if sq.tile.isSome:
+      echo lead, sq.tile.get
+    else:
+      echo lead, sq.camels
+  echo ""
+
+
+proc setState*(b: var Board; 
+              camels: openArray[tuple[c: Color, p: int]];
+              tiles: openArray[tuple[t: Tile, p: int]]) =
+  for (color, dest) in camels: # note that `camels` is ordered, as this determines stacking
+    b[dest].camels.add(color)
+    b.camels[color] = dest
+
+  for (tile, dest) in tiles:
+    b[dest].tile = some(tile)
+
+  let leadCamel = b[max(b.camels)].camels[^1] # top camel in the last currently-occupied space
+  b.leader = some(leadCamel)
+
+
+proc resetDice*(b: var Board) =
+  var d: array[Color, bool]
+  b.diceRolled = d
+
+
+proc advance*(b: var Board, die: Die) =
+  let
+    (color, roll) = die
+    startPos = b.camels[color]
+  var endPos = startPos + roll
+  
+  if endPos > 16: # camel has passed the finish line
+    b.leader = some(b[startPos].camels[^1])
+    b.gameOver = true
+    return
+
+  var prepend = false
+  if b[endPos].tile.isSome: # adjust position (and possibly stacking) to account for tile
+    let t = b[endPos].tile.get
+    endPos += int(t)
+    if t == tBackward: prepend = true
+
+  let stackStart = b[startPos].camels.find(color)
+  if prepend:
+    b[startPos].camels.moveSubstackPre(b[endPos].camels, stackStart)
+    let stackLen = b[startPos].camels.len - stackStart
+    for i in 0 ..< stackLen:
+      # we know how many camels we added to the bottom, so set the position for each of those
+      b.camels[b[endPos].camels[i]] = endPos
+  else:
+    let dstPrevHigh = b[endPos].camels.high
+    b[startPos].camels.moveSubstack(b[endPos].camels, stackStart)
+    # the camels that have moved start immediately after the previous high camel
+    for i in (dstPrevHigh + 1) .. b[endPos].camels.high:
+      b.camels[b[endPos].camels[i]] = endPos
+  
+  # if we are stacking on or moving past the previous leader
+  if endPos >= b.camels[b.leader.get]:
+    b.leader = some(b[endPos].camels[^1])
+  
+  b.diceRolled[color] = true

main.nim

@@ -1,29 +1,8 @@
-import math, hashes, options, tables, sequtils, sets, sugar
+import math, options, sequtils, sets, sugar
-import combinators, colors
+import combinators, game, fixedseq
-
-
-const allDice = @[cRed, cGreen, cBlue, cYellow, cPurple]
 
 
 type
-  Die* = tuple[color: Color, value: int]
-
-  Tile* = enum
-    tBackward = -1,
-    tForward = 1
-
-  Square* = object
-    camels: ColorStack
-    tile: Option[Tile]
-
-  Board* = object
-    squares: array[1..16, Square]
-    camels: array[Color, range[1..16]]
-    diceRolled: array[Color, bool]
-    leader: Option[Color]
-    gameOver: bool
-    initialized: bool
-
   ScoreSet* = array[Color, int]
 
   LegResults* = tuple[scores: ScoreSet, endStates: HashSet[Board]]
@@ -34,105 +13,14 @@ proc update*(scores: var ScoreSet, toAdd: ScoreSet) =
     scores[i] += s
 
 
-proc `[]`*[T](b: var Board, idx: T): var Square =
-  b.squares[idx]
-
-
-proc hash*(b: Board): Hash =
-  var h: Hash = 0
-  # there could be a tile anywhere so we have to check all squares
-  for i, sq in b.squares:
-    if sq.camels.len > 0 or sq.tile.isSome:
-      h = h !& i
-      if sq.tile.isSome:
-        h = h !& int(sq.tile.get) * 10 # so it isn't confused with a camel
-      else:
-        for c in sq.camels.asInt:
-          h = h !& c
-  result = !$h
-
-
-proc init*(b: var Board) =
-  for sq in b.squares.mitems:
-    sq.camels.init
-  b.initialized = true
-
-
-proc display(b: Board, start, stop: int) =
-  for i in start..stop:
-    let sq = b.squares[i]
-    let lead = $i & ": "
-    if sq.tile.isSome:
-      echo lead, sq.tile.get
-    else:
-      echo lead, sq.camels
-  echo ""
-
-
-proc setState(b: var Board; 
-              camels: openArray[tuple[c: Color, p: int]];
-              tiles: openArray[tuple[t: Tile, p: int]]) =
-  for (color, dest) in camels: # note that `camels` is ordered, as this determines stacking
-    b[dest].camels.add(color)
-    b.camels[color] = dest
-
-  for (tile, dest) in tiles:
-    b[dest].tile = some(tile)
-
-  let leadCamel = b[max(b.camels)].camels[^1] # top camel in the last currently-occupied space
-  b.leader = some(leadCamel)
-
-
-proc resetDice(b: var Board) =
-  var d: array[Color, bool]
-  b.diceRolled = d
-
-
-proc advance(b: var Board, die: Die) =
-  let
-    (color, roll) = die
-    startPos = b.camels[color]
-  var endPos = startPos + roll
-  
-  if endPos > 16: # camel has passed the finish line
-    b.leader = some(b[startPos].camels[^1])
-    b.gameOver = true
-    return
-
-  var prepend = false
-  if b[endPos].tile.isSome: # adjust position (and possibly stacking) to account for tile
-    let t = b[endPos].tile.get
-    endPos += int(t)
-    if t == tBackward: prepend = true
-
-  let stackStart = b[startPos].camels.find(color)
-  if prepend:
-    b[startPos].camels.moveSubstackPre(b[endPos].camels, stackStart)
-    let stackLen = b[startPos].camels.len - stackStart
-    for i in 0 ..< stackLen:
-      # we know how many camels we added to the bottom, so set the position for each of those
-      b.camels[b[endPos].camels[i]] = endPos
-  else:
-    let dstPrevHigh = b[endPos].camels.high
-    b[startPos].camels.moveSubstack(b[endPos].camels, stackStart)
-    # the camels that have moved start immediately after the previous high camel
-    for i in (dstPrevHigh + 1) .. b[endPos].camels.high:
-      b.camels[b[endPos].camels[i]] = endPos
-  
-  # if we are stacking on or moving past the previous leader
-  if endPos >= b.camels[b.leader.get]:
-    b.leader = some(b[endPos].camels[^1])
-  
-  b.diceRolled[color] = true
-
-
 proc projectLeg(b: Board): LegResults =
   var scores: ScoreSet
   var endStates: HashSet[Board]
 
-  let diceRemaining = collect(newSeq):
+  var diceRemaining: ColorStack
+  diceRemaining.initFixedSeq
   for i, c in b.diceRolled:
-      if not c: i
+    if not c: diceRemaining.add(i)
 
   for future in possibleFutures(diceRemaining):
     var prediction = b # make a copy
@@ -174,6 +62,14 @@ b.display(1, 5)
 # b.advance((cRed, 1))
 # b.display(1, 5)
 
+# var s: ColorStack
+# s.initFixedSeq
+# for i in 0..4:
+#   s.add(Color(i))
+
+# echo s
+# echo s[2]
+
 let r = b.projectOutcomes(2)
 let total = r.sum
 for i, c in r: