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authorKartik K. Agaram <vc@akkartik.com>2016-03-14 01:00:48 -0700
committerKartik K. Agaram <vc@akkartik.com>2016-03-14 01:00:48 -0700
commit2badd89a58b9666563746d71069abf16f05709ea (patch)
tree779c9feb243fc8d0f33051cd8323fd23f912f373 /076duplex_list.mu
parent8b095f802129f8c328a3a4dc3de4443890d34d59 (diff)
downloadmu-2badd89a58b9666563746d71069abf16f05709ea.tar.gz
2778 - fix all layers
Diffstat (limited to '076duplex_list.mu')
-rw-r--r--076duplex_list.mu526
1 files changed, 526 insertions, 0 deletions
diff --git a/076duplex_list.mu b/076duplex_list.mu
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+# A doubly linked list permits bidirectional traversal.
+
+container duplex-list:_elem [
+  value:_elem
+  next:address:shared:duplex-list:_elem
+  prev:address:shared:duplex-list:_elem
+]
+
+# should I say in/contained-in:result, allow ingredients to refer to products?
+def push x:_elem, in:address:shared:duplex-list:_elem -> in:address:shared:duplex-list:_elem [
+  local-scope
+  load-ingredients
+  result:address:shared:duplex-list:_elem <- new {(duplex-list _elem): type}
+  val:address:_elem <- get-address *result, value:offset
+  *val <- copy x
+  next:address:address:shared:duplex-list:_elem <- get-address *result, next:offset
+  *next <- copy in
+  {
+    break-unless in
+    prev:address:address:shared:duplex-list:_elem <- get-address *in, prev:offset
+    *prev <- copy result
+  }
+  return result  # needed explicitly because we need to replace 'in' with 'result'
+]
+
+def first in:address:shared:duplex-list:_elem -> result:_elem [
+  local-scope
+  load-ingredients
+  return-unless in, 0
+  result <- get *in, value:offset
+]
+
+def next in:address:shared:duplex-list:_elem -> result:address:shared:duplex-list:_elem/contained-in:in [
+  local-scope
+  load-ingredients
+  return-unless in, 0
+  result <- get *in, next:offset
+]
+
+def prev in:address:shared:duplex-list:_elem -> result:address:shared:duplex-list:_elem/contained-in:in [
+  local-scope
+  load-ingredients
+  return-unless in, 0
+  result <- get *in, prev:offset
+  return result
+]
+
+scenario duplex-list-handling [
+  run [
+    # reserve locations 0, 1 and 2 to check for missing null check
+    1:number <- copy 34
+    2:number <- copy 35
+    3:address:shared:duplex-list:character <- push 3, 0
+    3:address:shared:duplex-list:character <- push 4, 3:address:shared:duplex-list:character
+    3:address:shared:duplex-list:character <- push 5, 3:address:shared:duplex-list:character
+    4:address:shared:duplex-list:character <- copy 3:address:shared:duplex-list:character
+    5:character <- first 4:address:shared:duplex-list:character
+    4:address:shared:duplex-list:character <- next 4:address:shared:duplex-list:character
+    6:character <- first 4:address:shared:duplex-list:character
+    4:address:shared:duplex-list:character <- next 4:address:shared:duplex-list:character
+    7:character <- first 4:address:shared:duplex-list:character
+    8:address:shared:duplex-list:character <- next 4:address:shared:duplex-list:character
+    9:character <- first 8:address:shared:duplex-list:character
+    10:address:shared:duplex-list:character <- next 8:address:shared:duplex-list:character
+    11:address:shared:duplex-list:character <- prev 8:address:shared:duplex-list:character
+    4:address:shared:duplex-list:character <- prev 4:address:shared:duplex-list:character
+    12:character <- first 4:address:shared:duplex-list:character
+    4:address:shared:duplex-list:character <- prev 4:address:shared:duplex-list:character
+    13:character <- first 4:address:shared:duplex-list:character
+    14:boolean <- equal 3:address:shared:duplex-list:character, 4:address:shared:duplex-list:character
+  ]
+  memory-should-contain [
+    0 <- 0  # no modifications to null pointers
+    1 <- 34
+    2 <- 35
+    5 <- 5  # scanning next
+    6 <- 4
+    7 <- 3
+    8 <- 0  # null
+    9 <- 0  # first of null
+    10 <- 0  # next of null
+    11 <- 0  # prev of null
+    12 <- 4  # then start scanning prev
+    13 <- 5
+    14 <- 1  # list back at start
+  ]
+]
+
+# insert 'x' after 'in'
+def insert x:_elem, in:address:shared:duplex-list:_elem -> in:address:shared:duplex-list:_elem [
+  local-scope
+  load-ingredients
+  new-node:address:shared:duplex-list:_elem <- new {(duplex-list _elem): type}
+  val:address:_elem <- get-address *new-node, value:offset
+  *val <- copy x
+  next-node:address:shared:duplex-list:_elem <- get *in, next:offset
+  # in.next = new-node
+  y:address:address:shared:duplex-list:_elem <- get-address *in, next:offset
+  *y <- copy new-node
+  # new-node.prev = in
+  y <- get-address *new-node, prev:offset
+  *y <- copy in
+  # new-node.next = next-node
+  y <- get-address *new-node, next:offset
+  *y <- copy next-node
+  # if next-node is not null
+  return-unless next-node
+  # next-node.prev = new-node
+  y <- get-address *next-node, prev:offset
+  *y <- copy new-node
+]
+
+scenario inserting-into-duplex-list [
+  run [
+    1:address:shared:duplex-list:character <- push 3, 0
+    1:address:shared:duplex-list:character <- push 4, 1:address:shared:duplex-list:character
+    1:address:shared:duplex-list:character <- push 5, 1:address:shared:duplex-list:character
+    2:address:shared:duplex-list:character <- next 1:address:shared:duplex-list:character  # 2 points inside list
+    2:address:shared:duplex-list:character <- insert 6, 2:address:shared:duplex-list:character
+    # check structure like before
+    2:address:shared:duplex-list:character <- copy 1:address:shared:duplex-list:character
+    3:character <- first 2:address:shared:duplex-list:character
+    2:address:shared:duplex-list:character <- next 2:address:shared:duplex-list:character
+    4:character <- first 2:address:shared:duplex-list:character
+    2:address:shared:duplex-list:character <- next 2:address:shared:duplex-list:character
+    5:character <- first 2:address:shared:duplex-list:character
+    2:address:shared:duplex-list:character <- next 2:address:shared:duplex-list:character
+    6:character <- first 2:address:shared:duplex-list:character
+    2:address:shared:duplex-list:character <- prev 2:address:shared:duplex-list:character
+    7:character <- first 2:address:shared:duplex-list:character
+    2:address:shared:duplex-list:character <- prev 2:address:shared:duplex-list:character
+    8:character <- first 2:address:shared:duplex-list:character
+    2:address:shared:duplex-list:character <- prev 2:address:shared:duplex-list:character
+    9:character <- first 2:address:shared:duplex-list:character
+    10:boolean <- equal 1:address:shared:duplex-list:character, 2:address:shared:duplex-list:character
+  ]
+  memory-should-contain [
+    3 <- 5  # scanning next
+    4 <- 4
+    5 <- 6  # inserted element
+    6 <- 3
+    7 <- 6  # then prev
+    8 <- 4
+    9 <- 5
+    10 <- 1  # list back at start
+  ]
+]
+
+scenario inserting-at-end-of-duplex-list [
+  run [
+    1:address:shared:duplex-list:character <- push 3, 0
+    1:address:shared:duplex-list:character <- push 4, 1:address:shared:duplex-list:character
+    1:address:shared:duplex-list:character <- push 5, 1:address:shared:duplex-list:character
+    2:address:shared:duplex-list:character <- next 1:address:shared:duplex-list:character  # 2 points inside list
+    2:address:shared:duplex-list:character <- next 2:address:shared:duplex-list:character  # now at end of list
+    2:address:shared:duplex-list:character <- insert 6, 2:address:shared:duplex-list:character
+    # check structure like before
+    2:address:shared:duplex-list:character <- copy 1:address:shared:duplex-list:character
+    3:character <- first 2:address:shared:duplex-list:character
+    2:address:shared:duplex-list:character <- next 2:address:shared:duplex-list:character
+    4:character <- first 2:address:shared:duplex-list:character
+    2:address:shared:duplex-list:character <- next 2:address:shared:duplex-list:character
+    5:character <- first 2:address:shared:duplex-list:character
+    2:address:shared:duplex-list:character <- next 2:address:shared:duplex-list:character
+    6:character <- first 2:address:shared:duplex-list:character
+    2:address:shared:duplex-list:character <- prev 2:address:shared:duplex-list:character
+    7:character <- first 2:address:shared:duplex-list:character
+    2:address:shared:duplex-list:character <- prev 2:address:shared:duplex-list:character
+    8:character <- first 2:address:shared:duplex-list:character
+    2:address:shared:duplex-list:character <- prev 2:address:shared:duplex-list:character
+    9:character <- first 2:address:shared:duplex-list:character
+    10:boolean <- equal 1:address:shared:duplex-list:character, 2:address:shared:duplex-list:character
+  ]
+  memory-should-contain [
+    3 <- 5  # scanning next
+    4 <- 4
+    5 <- 3
+    6 <- 6  # inserted element
+    7 <- 3  # then prev
+    8 <- 4
+    9 <- 5
+    10 <- 1  # list back at start
+  ]
+]
+
+scenario inserting-after-start-of-duplex-list [
+  run [
+    1:address:shared:duplex-list:character <- push 3, 0
+    1:address:shared:duplex-list:character <- push 4, 1:address:shared:duplex-list:character
+    1:address:shared:duplex-list:character <- push 5, 1:address:shared:duplex-list:character
+    1:address:shared:duplex-list:character <- insert 6, 1:address:shared:duplex-list:character
+    # check structure like before
+    2:address:shared:duplex-list:character <- copy 1:address:shared:duplex-list:character
+    3:character <- first 2:address:shared:duplex-list:character
+    2:address:shared:duplex-list:character <- next 2:address:shared:duplex-list:character
+    4:character <- first 2:address:shared:duplex-list:character
+    2:address:shared:duplex-list:character <- next 2:address:shared:duplex-list:character
+    5:character <- first 2:address:shared:duplex-list:character
+    2:address:shared:duplex-list:character <- next 2:address:shared:duplex-list:character
+    6:character <- first 2:address:shared:duplex-list:character
+    2:address:shared:duplex-list:character <- prev 2:address:shared:duplex-list:character
+    7:character <- first 2:address:shared:duplex-list:character
+    2:address:shared:duplex-list:character <- prev 2:address:shared:duplex-list:character
+    8:character <- first 2:address:shared:duplex-list:character
+    2:address:shared:duplex-list:character <- prev 2:address:shared:duplex-list:character
+    9:character <- first 2:address:shared:duplex-list:character
+    10:boolean <- equal 1:address:shared:duplex-list:character, 2:address:shared:duplex-list:character
+  ]
+  memory-should-contain [
+    3 <- 5  # scanning next
+    4 <- 6  # inserted element
+    5 <- 4
+    6 <- 3
+    7 <- 4  # then prev
+    8 <- 6
+    9 <- 5
+    10 <- 1  # list back at start
+  ]
+]
+
+# remove 'x' from its surrounding list 'in'
+#
+# Returns null if and only if list is empty. Beware: in that case any other
+# pointers to the head are now invalid.
+def remove x:address:shared:duplex-list:_elem/contained-in:in, in:address:shared:duplex-list:_elem -> in:address:shared:duplex-list:_elem [
+  local-scope
+  load-ingredients
+  # if 'x' is null, return
+  return-unless x
+  next-node:address:shared:duplex-list:_elem <- get *x, next:offset
+  prev-node:address:shared:duplex-list:_elem <- get *x, prev:offset
+  # null x's pointers
+  tmp:address:address:shared:duplex-list:_elem <- get-address *x, next:offset
+  *tmp <- copy 0
+  tmp <- get-address *x, prev:offset
+  *tmp <- copy 0
+  # if next-node is not null, set its prev pointer
+  {
+    break-unless next-node
+    tmp <- get-address *next-node, prev:offset
+    *tmp <- copy prev-node
+  }
+  # if prev-node is not null, set its next pointer and return
+  {
+    break-unless prev-node
+    tmp <- get-address *prev-node, next:offset
+    *tmp <- copy next-node
+    return
+  }
+  # if prev-node is null, then we removed the node at 'in'
+  # return the new head rather than the old 'in'
+  return next-node
+]
+
+scenario removing-from-duplex-list [
+  run [
+    1:address:shared:duplex-list:character <- push 3, 0
+    1:address:shared:duplex-list:character <- push 4, 1:address:shared:duplex-list:character
+    1:address:shared:duplex-list:character <- push 5, 1:address:shared:duplex-list:character
+    2:address:shared:duplex-list:character <- next 1:address:shared:duplex-list:character  # 2 points at second element
+    1:address:shared:duplex-list:character <- remove 2:address:shared:duplex-list:character, 1:address:shared:duplex-list:character
+    3:boolean <- equal 2:address:shared:duplex-list:character, 0
+    # check structure like before
+    2:address:shared:duplex-list:character <- copy 1:address:shared:duplex-list:character
+    4:character <- first 2:address:shared:duplex-list:character
+    2:address:shared:duplex-list:character <- next 2:address:shared:duplex-list:character
+    5:character <- first 2:address:shared:duplex-list:character
+    6:address:shared:duplex-list:character <- next 2:address:shared:duplex-list:character
+    2:address:shared:duplex-list:character <- prev 2:address:shared:duplex-list:character
+    7:character <- first 2:address:shared:duplex-list:character
+    8:boolean <- equal 1:address:shared:duplex-list:character, 2:address:shared:duplex-list:character
+  ]
+  memory-should-contain [
+    3 <- 0  # remove returned non-null
+    4 <- 5  # scanning next, skipping deleted element
+    5 <- 3
+    6 <- 0  # no more elements
+    7 <- 5  # prev of final element
+    8 <- 1  # list back at start
+  ]
+]
+
+scenario removing-from-start-of-duplex-list [
+  run [
+    1:address:shared:duplex-list:character <- push 3, 0
+    1:address:shared:duplex-list:character <- push 4, 1:address:shared:duplex-list:character
+    1:address:shared:duplex-list:character <- push 5, 1:address:shared:duplex-list:character
+    1:address:shared:duplex-list:character <- remove 1:address:shared:duplex-list:character, 1:address:shared:duplex-list:character
+    # check structure like before
+    2:address:shared:duplex-list:character <- copy 1:address:shared:duplex-list:character
+    3:character <- first 2:address:shared:duplex-list:character
+    2:address:shared:duplex-list:character <- next 2:address:shared:duplex-list:character
+    4:character <- first 2:address:shared:duplex-list:character
+    5:address:shared:duplex-list:character <- next 2:address:shared:duplex-list:character
+    2:address:shared:duplex-list:character <- prev 2:address:shared:duplex-list:character
+    6:character <- first 2:address:shared:duplex-list:character
+    7:boolean <- equal 1:address:shared:duplex-list:character, 2:address:shared:duplex-list:character
+  ]
+  memory-should-contain [
+    3 <- 4  # scanning next, skipping deleted element
+    4 <- 3
+    5 <- 0  # no more elements
+    6 <- 4  # prev of final element
+    7 <- 1  # list back at start
+  ]
+]
+
+scenario removing-from-end-of-duplex-list [
+  run [
+    1:address:shared:duplex-list:character <- push 3, 0
+    1:address:shared:duplex-list:character <- push 4, 1:address:shared:duplex-list:character
+    1:address:shared:duplex-list:character <- push 5, 1:address:shared:duplex-list:character
+    # delete last element
+    2:address:shared:duplex-list:character <- next 1:address:shared:duplex-list:character
+    2:address:shared:duplex-list:character <- next 2:address:shared:duplex-list:character
+    1:address:shared:duplex-list:character <- remove 2:address:shared:duplex-list:character, 1:address:shared:duplex-list:character
+    3:boolean <- equal 2:address:shared:duplex-list:character, 0
+    # check structure like before
+    2:address:shared:duplex-list:character <- copy 1:address:shared:duplex-list:character
+    4:character <- first 2:address:shared:duplex-list:character
+    2:address:shared:duplex-list:character <- next 2:address:shared:duplex-list:character
+    5:character <- first 2:address:shared:duplex-list:character
+    6:address:shared:duplex-list:character <- next 2:address:shared:duplex-list:character
+    2:address:shared:duplex-list:character <- prev 2:address:shared:duplex-list:character
+    7:character <- first 2:address:shared:duplex-list:character
+    8:boolean <- equal 1:address:shared:duplex-list:character, 2:address:shared:duplex-list:character
+  ]
+  memory-should-contain [
+    3 <- 0  # remove returned non-null
+    4 <- 5  # scanning next, skipping deleted element
+    5 <- 4
+    6 <- 0  # no more elements
+    7 <- 5  # prev of final element
+    8 <- 1  # list back at start
+  ]
+]
+
+scenario removing-from-singleton-list [
+  run [
+    1:address:shared:duplex-list:character <- push 3, 0
+    1:address:shared:duplex-list:character <- remove 1:address:shared:duplex-list:character, 1:address:shared:duplex-list:character
+  ]
+  memory-should-contain [
+    1 <- 0  # back to an empty list
+  ]
+]
+
+# remove values between 'start' and 'end' (both exclusive)
+# also clear pointers back out from start/end for hygiene
+def remove-between start:address:shared:duplex-list:_elem, end:address:shared:duplex-list:_elem/contained-in:start -> start:address:shared:duplex-list:_elem [
+  local-scope
+  load-ingredients
+  return-unless start
+  # start->next->prev = 0
+  # start->next = end
+  next:address:address:shared:duplex-list:_elem <- get-address *start, next:offset
+  nothing-to-delete?:boolean <- equal *next, end
+  return-if nothing-to-delete?
+  prev:address:address:shared:duplex-list:_elem <- get-address **next, prev:offset
+  *prev <- copy 0
+  *next <- copy end
+  return-unless end
+  # end->prev->next = 0
+  # end->prev = start
+  prev <- get-address *end, prev:offset
+  next <- get-address **prev, next:offset
+  *next <- copy 0
+  *prev <- copy start
+]
+
+scenario remove-range [
+  # construct a duplex list with six elements [13, 14, 15, 16, 17, 18]
+  1:address:shared:duplex-list:character <- push 18, 0
+  1:address:shared:duplex-list:character <- push 17, 1:address:shared:duplex-list:character
+  1:address:shared:duplex-list:character <- push 16, 1:address:shared:duplex-list:character
+  1:address:shared:duplex-list:character <- push 15, 1:address:shared:duplex-list:character
+  1:address:shared:duplex-list:character <- push 14, 1:address:shared:duplex-list:character
+  1:address:shared:duplex-list:character <- push 13, 1:address:shared:duplex-list:character
+  run [
+    # delete 16 onwards
+    # first pointer: to the third element
+    2:address:shared:duplex-list:character <- next 1:address:shared:duplex-list:character
+    2:address:shared:duplex-list:character <- next 2:address:shared:duplex-list:character
+    2:address:shared:duplex-list:character <- remove-between 2:address:shared:duplex-list:character, 0
+    # now check the list
+    4:character <- get *1:address:shared:duplex-list:character, value:offset
+    5:address:shared:duplex-list:character <- next 1:address:shared:duplex-list:character
+    6:character <- get *5:address:shared:duplex-list:character, value:offset
+    7:address:shared:duplex-list:character <- next 5:address:shared:duplex-list:character
+    8:character <- get *7:address:shared:duplex-list:character, value:offset
+    9:address:shared:duplex-list:character <- next 7:address:shared:duplex-list:character
+  ]
+  memory-should-contain [
+    4 <- 13
+    6 <- 14
+    8 <- 15
+    9 <- 0
+  ]
+]
+
+scenario remove-range-to-end [
+  # construct a duplex list with six elements [13, 14, 15, 16, 17, 18]
+  1:address:shared:duplex-list:character <- push 18, 0
+  1:address:shared:duplex-list:character <- push 17, 1:address:shared:duplex-list:character
+  1:address:shared:duplex-list:character <- push 16, 1:address:shared:duplex-list:character
+  1:address:shared:duplex-list:character <- push 15, 1:address:shared:duplex-list:character
+  1:address:shared:duplex-list:character <- push 14, 1:address:shared:duplex-list:character
+  1:address:shared:duplex-list:character <- push 13, 1:address:shared:duplex-list:character
+  run [
+    # delete 15, 16 and 17
+    # first pointer: to the third element
+    2:address:shared:duplex-list:character <- next 1:address:shared:duplex-list:character
+    # second pointer: to the fifth element
+    3:address:shared:duplex-list:character <- next 2:address:shared:duplex-list:character
+    3:address:shared:duplex-list:character <- next 3:address:shared:duplex-list:character
+    3:address:shared:duplex-list:character <- next 3:address:shared:duplex-list:character
+    3:address:shared:duplex-list:character <- next 3:address:shared:duplex-list:character
+    remove-between 2:address:shared:duplex-list:character, 3:address:shared:duplex-list:character
+    # now check the list
+    4:character <- get *1:address:shared:duplex-list:character, value:offset
+    5:address:shared:duplex-list:character <- next 1:address:shared:duplex-list:character
+    6:character <- get *5:address:shared:duplex-list:character, value:offset
+    7:address:shared:duplex-list:character <- next 5:address:shared:duplex-list:character
+    8:character <- get *7:address:shared:duplex-list:character, value:offset
+    9:address:shared:duplex-list:character <- next 7:address:shared:duplex-list:character
+  ]
+  memory-should-contain [
+    4 <- 13
+    6 <- 14
+    8 <- 18
+    9 <- 0
+  ]
+]
+
+scenario remove-range-empty [
+  # construct a duplex list with six elements [13, 14, 15, 16, 17, 18]
+  1:address:shared:duplex-list:character <- push 14, 0
+  1:address:shared:duplex-list:character <- push 13, 1:address:shared:duplex-list:character
+  run [
+    # delete 16 onwards
+    # first pointer: to the third element
+    2:address:shared:duplex-list:character <- next 1:address:shared:duplex-list:character
+    remove-between 1:address:shared:duplex-list:character, 2:address:shared:duplex-list:character
+    # now check the list
+    4:character <- get *1:address:shared:duplex-list:character, value:offset
+    5:address:shared:duplex-list:character <- next 1:address:shared:duplex-list:character
+    6:character <- get *5:address:shared:duplex-list:character, value:offset
+    7:address:shared:duplex-list:character <- next 5:address:shared:duplex-list:character
+  ]
+  memory-should-contain [
+    4 <- 13
+    6 <- 14
+    7 <- 0
+  ]
+]
+
+# insert list beginning at 'new' after 'in'
+def insert-range in:address:shared:duplex-list:_elem, start:address:shared:duplex-list:_elem/contained-in:in -> in:address:shared:duplex-list:_elem [
+  local-scope
+  load-ingredients
+  return-unless in
+  return-unless start
+  end:address:shared:duplex-list:_elem <- copy start
+  {
+    next:address:shared:duplex-list:_elem <- next end/insert-range
+    break-unless next
+    end <- copy next
+    loop
+  }
+  next:address:shared:duplex-list:_elem <- next in
+  dest:address:address:shared:duplex-list:_elem <- get-address *end, next:offset
+  *dest <- copy next
+  {
+    break-unless next
+    dest <- get-address *next, prev:offset
+    *dest <- copy end
+  }
+  dest <- get-address *in, next:offset
+  *dest <- copy start
+  dest <- get-address *start, prev:offset
+  *dest <- copy in
+]
+
+def append in:address:shared:duplex-list:_elem, new:address:shared:duplex-list:_elem/contained-in:in -> in:address:shared:duplex-list:_elem [
+  local-scope
+  load-ingredients
+  last:address:shared:duplex-list:_elem <- last in
+  dest:address:address:shared:duplex-list:_elem <- get-address *last, next:offset
+  *dest <- copy new
+  return-unless new
+  dest <- get-address *new, prev:offset
+  *dest <- copy last
+]
+
+def last in:address:shared:duplex-list:_elem -> result:address:shared:duplex-list:_elem [
+  local-scope
+  load-ingredients
+  result <- copy in
+  {
+    next:address:shared:duplex-list:_elem <- next result
+    break-unless next
+    result <- copy next
+    loop
+  }
+]
+
+# helper for debugging
+def dump-from x:address:shared:duplex-list:_elem [
+  local-scope
+  load-ingredients
+  $print x, [: ]
+  {
+    break-unless x
+    c:_elem <- get *x, value:offset
+    $print c, [ ]
+    x <- next x
+    {
+      is-newline?:boolean <- equal c, 10/newline
+      break-unless is-newline?
+      $print 10/newline
+      $print x, [: ]
+    }
+    loop
+  }
+  $print 10/newline, [---], 10/newline
+]