progress creating a rope (rope.sml) which holds line metadata
This commit is contained in:
495
rope.sml
495
rope.sml
@@ -3,11 +3,7 @@ sig
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type t
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val empty: t
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val fromString: string -> t
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val size: t -> int
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val insert: int * string * t -> t
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val append: string * t -> t
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val delete: int * int * t -> t
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val toString: t -> string
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val foldr: ('a * string * int vector -> 'a) * 'a * t -> 'a
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end
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structure Rope :> ROPE =
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@@ -44,57 +40,128 @@ struct
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fun countLineBreaks str =
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helpCountLineBreaks (String.size str - 1, [], str)
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(* Binary search. Used to find split point in vector. *)
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fun binSearch (findNum, lines, low, high) =
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if Vector.length lines = 0 then
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0
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else
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let
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val mid = low + ((high - low) div 2)
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in
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if high >= low then
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let
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val midVal = Vector.sub (lines, mid)
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in
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if midVal = findNum then
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mid
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else if midVal < findNum then
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binSearch (findNum, lines, mid + 1, high)
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else
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binSearch (findNum, lines, low, mid - 1)
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end
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else
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mid
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end
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datatype t =
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N0 of string
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N0 of string * int vector
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| N1 of t
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| N2 of t * int * t
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| L2 of string * string
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| N2 of t * int * int * t
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| L2 of string * int vector * string * int vector
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| N3 of t * t * t
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exception AuxConstructor
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exception Substring of int
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fun foldrString (f, state, rope) =
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case rope of
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N2 (l, _, _, r) =>
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let val state = foldrString (f, state, r)
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in foldrString (f, state, l)
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end
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| N1 t => foldrString (f, state, t)
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| N0 (s, _) => f (state, s)
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| _ => raise AuxConstructor
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fun toString rope =
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let val strList = foldrString ((fn (acc, str) => str :: acc), [], rope)
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in String.concat strList
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end
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fun foldr (f, state, rope) =
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case rope of
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N2 (l, _, r) =>
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N2 (l, _, _, r) =>
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let val state = foldr (f, state, r)
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in foldr (f, state, l)
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end
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| N1 t => foldr (f, state, t)
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| N0 s => f (state, s)
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| N0 (s, v) => f (state, s, v)
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| _ => raise AuxConstructor
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fun toString rope =
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let val strList = foldr ((fn (acc, str) => str :: acc), [], rope)
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in String.concat strList
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end
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datatype balance = AddedNode | DeletedNode | NoAction
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val targetLength = 1024
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val empty = N0 ""
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fun fromString string = N0 string
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val targetVecLength = 128
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fun isLessThanTarget (str1, str2) =
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fun id x = x
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val emptyVec = Vector.tabulate (0, id)
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val empty = N0 ("", emptyVec)
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fun fromString string =
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let val lineBreaks = countLineBreaks string
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in N0 (string, lineBreaks)
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end
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fun isLessThanTarget (str1, str2, vec1, vec2) =
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String.size str1 + String.size str2 <= targetLength
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andalso Vector.length vec1 + Vector.length vec2 <= targetVecLength
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fun helpSize (acc, rope) =
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(* This function creates a new node in the rope, calculating right-metadata.
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* This is equivalent to helpSize/size in tiny_rope.ml,
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* but because the size function in tiny_rope.ml was only used
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* by callers to construct N2 cases,
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* it can be replaced with a function that constructs N2 cases
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* instead of returning (int * int) metadata which results in
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* an extra tuple allocation. *)
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fun helpMakeN2 (idxAcc, lineAcc, left, right, rope) =
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case rope of
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N0 s => acc + String.size s
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| N1 t => helpSize (acc, t)
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| N2 (_, lm, r) => helpSize (acc + lm, r)
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N2 (_, lms, lmv, r) =>
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helpMakeN2 (lms + idxAcc, lmv + lineAcc, left, right, r)
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| N1 t => helpMakeN2 (idxAcc, lineAcc, left, right, t)
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| N0 (str, lines) =>
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let
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val idxAcc = idxAcc + String.size str
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val lineAcc = lineAcc + Vector.length lines
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in
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N2 (left, idxAcc, lineAcc, right)
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end
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| _ => raise AuxConstructor
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fun size rope = helpSize (0, rope)
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(* Accumulate right-metadata for left rope. *)
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fun makeN2 (left, right) =
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helpMakeN2 (0, 0, left, right, left)
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fun insL2 (s1, v1, s2, v2) =
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let
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val left = N0 (s1, v1)
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val right = N0 (s2, v2)
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in
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N2 (left, String.size s1, Vector.length v1, right)
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end
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fun insN3 (t1, t2, t3) =
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let
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val left = makeN2 (t1, t2)
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val right = N1 t3
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in
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makeN2 (left, right)
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end
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fun insRoot rope =
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case rope of
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L2 (s1, s2) => N2 (N0 s1, String.size s1, N0 s2)
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| N3 (t1, t2, t3) =>
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let val left = N2 (t1, size t1, t2)
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in N2 (left, size left, N1 t3)
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end
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L2 (s1, v1, s2, v2) => insL2 (s1, v1, s2, v2)
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| N3 (t1, t2, t3) => insN3 (t1, t2, t3)
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| t => t
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fun delRoot rope =
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@@ -104,285 +171,247 @@ struct
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fun insN1 rope =
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case rope of
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L2 (s1, s2) => N2 (N0 s1, String.size s1, N0 s2)
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| N3 (t1, t2, t3) =>
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let val left = N2 (t1, size t1, t2)
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in N2 (left, size left, N1 t3)
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end
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L2 (s1, v1, s2, v2) => insL2 (s1, v1, s2, v2)
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| N3 (t1, t2, t3) => insN3 (t1, t2, t3)
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| t => N1 t
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fun insN2Left (left, right) =
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case (left, right) of
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(L2 (s1, s2), t3) => N3 (N0 s1, N0 s2, t3)
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(L2 (s1, v1, s2, v2), t3) =>
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let
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val left = N0 (s1, v1)
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val middle = N0 (s2, v2)
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in
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N3 (left, middle, t3)
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end
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| (N3 (t1, t2, t3), N1 t4) =>
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let
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val left = N2 (t1, size t1, t2)
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val right = N2 (t3, size t3, t4)
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val left = makeN2 (t1, t2)
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val right = makeN2 (t3, t4)
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in
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N2 (left, size left, right)
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makeN2 (left, right)
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end
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| (N3 (t1, t2, t3), t4) =>
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let val left = N2 (t1, size t1, t2)
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in N3 (left, N1 t3, t4)
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let
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val left = makeN2 (t1, t2)
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val middle = N1 t3
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in
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N3 (left, middle, t4)
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end
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| (l, r) => N2 (l, size l, r)
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| (l, r) => makeN2 (l, r)
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fun delN2Left (left, right) =
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case (left, right) of
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(N1 t1, N1 t2) => N1 (N2 (t1, size t1, t2))
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| (N1 (N1 t1), N2 (N1 t2, _, (t3 as N2 _))) =>
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(N1 t1, N1 t2) => let val inner = makeN2 (t1, t2) in N1 inner end
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| (N1 (N1 t1), N2 (N1 t2, _, _, (t3 as N2 _))) =>
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let
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val left = N2 (t1, size t1, t2)
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val inner = N2 (left, size left, t3)
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val left = makeN2 (t1, t2)
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val inner = makeN2 (left, t3)
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in
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N1 inner
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end
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| (N1 (N1 t1), N2 (N2 (t2, _, t3), _, N1 t4)) =>
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| (N1 (N1 t1), N2 (N2 (t2, _, _, t3), _, _, N1 t4)) =>
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let
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val left = N2 (t1, size t1, t2)
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val right = N2 (t3, size t3, t4)
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val inner = N2 (left, size left, right)
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val left = makeN2 (t1, t2)
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val right = makeN2 (t3, t4)
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val inner = makeN2 (left, right)
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in
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N1 inner
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end
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| (N1 (t1 as N1 _), N2 ((t2 as N2 _), _, (t3 as N2 _))) =>
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| (N1 (t1 as N1 _), N2 ((t2 as N2 _), _, _, (t3 as N2 _))) =>
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let
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val left = N2 (t1, size t1, t2)
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val left = makeN2 (t1, t2)
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val right = N1 t3
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in
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N2 (left, size left, right)
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makeN2 (left, right)
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end
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| (l, r) => N2 (l, size l, r)
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| (l, r) => makeN2 (l, r)
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fun insN2Right (left, right) =
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case (left, right) of
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(t1, L2 (s1, s2)) => N3 (t1, N0 s1, N0 s2)
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(t1, L2 (s1, v1, s2, v2)) =>
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let
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val middle = N0 (s1, v1)
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val right = N0 (s2, v2)
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in
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N3 (t1, middle, right)
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end
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| (N1 t1, N3 (t2, t3, t4)) =>
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let
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val left = N2 (t1, size t1, t2)
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val right = N2 (t3, size t3, t4)
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val left = makeN2 (t1, t2)
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val right = makeN2 (t3, t4)
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in
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N2 (left, size left, right)
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makeN2 (left, right)
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end
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| (t1, N3 (t2, t3, t4)) =>
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let val right = N2 (t3, size t3, t4)
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in N3 (t1, N1 t2, right)
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let
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val right = makeN2 (t3, t4)
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val middle = N1 t2
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in
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N3 (t1, middle, right)
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end
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| (l, r) => N2 (l, size l, r)
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| (l, r) => makeN2 (l, r)
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fun delN2Right (left, right) =
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case (left, right) of
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(N2 (N1 t1, _, N2 (t2, _, t3)), N1 (N1 t4)) =>
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(N2 (N1 t1, _, _, N2 (t2, _, _, t3)), N1 (N1 t4)) =>
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let
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val left = N2 (t1, size t1, t2)
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val right = N2 (t3, size t3, t4)
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val inner = N2 (left, size left, right)
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val left = makeN2 (t1, t2)
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val right = makeN2 (t3, t4)
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val inner = makeN2 (left, right)
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in
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N1 inner
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end
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| (N2 ((t1 as N2 _), lm, N1 t2), N1 (N1 t3)) =>
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| (N2 ((t1 as N2 _), lms, lmv, N1 t2), N1 (N1 t3)) =>
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let
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val right = N2 (t2, size t2, t3)
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val inner = N2 (t1, lm, right)
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val right = makeN2 (t2, t3)
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val inner = N2 (t1, lms, lmv, right)
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in
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N1 inner
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end
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| (N2 ((t1 as N2 _), _, (t2 as N2 _)), N1 (t3 as N1 _)) =>
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| (N2 ((t1 as N2 _), _, _, (t2 as N2 _)), N1 (t3 as N1 _)) =>
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let
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val left = N1 t1
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val right = N2 (t2, size t2, t3)
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val right = makeN2 (t2, t3)
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in
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N2 (left, size left, right)
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makeN2 (left, right)
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end
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| (l, r) => N2 (l, size l, r)
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| (l, r) => makeN2 (l, r)
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fun insLeaf (curIdx, newStr, rope, oldStr) =
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fun insVecBefore (oldVec, newVec, newStr) =
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let
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val oldLen = Vector.length oldVec
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val newLen = Vector.length newVec
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val total = oldLen + newLen
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val newStrLen = String.size newStr
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in
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Vector.tabulate (total, (fn (idx) =>
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if idx < newLen then Vector.sub (newVec, idx)
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else Vector.sub (oldVec, idx - newLen) + newStrLen))
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end
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fun insVecAfter (oldStr, oldVec, newVec) =
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let
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val oldLen = Vector.length oldVec
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val newLen = Vector.length newVec
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val total = oldLen + newLen
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val oldStrLen = String.size oldStr
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in
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Vector.tabulate (total, (fn (idx) =>
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if idx < oldLen then Vector.sub (oldVec, idx)
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else Vector.sub (newVec, idx - oldLen) + oldStrLen))
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end
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fun insLeaf (curIdx, newStr, newVec, rope, oldStr, oldVec) =
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if curIdx <= 0 then
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if isLessThanTarget (oldStr, newStr) then (N0 (newStr ^ oldStr), NoAction)
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else (L2 (newStr, oldStr), AddedNode)
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if isLessThanTarget (oldStr, newStr, oldVec, newVec) then
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let
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val str = newStr ^ oldStr
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val vec = insVecBefore (oldVec, newVec, newStr)
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in
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(N0 (str, vec), NoAction)
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end
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else
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let val l2 = L2 (newStr, newVec, oldStr, oldVec)
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in (l2, AddedNode)
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end
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else if curIdx >= String.size oldStr then
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if isLessThanTarget (oldStr, newStr) then (N0 (oldStr ^ newStr), NoAction)
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else (L2 (oldStr, newStr), AddedNode)
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if isLessThanTarget (oldStr, newStr, oldVec, newVec) then
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let
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val str = oldStr ^ newStr
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val vec = insVecAfter (oldStr, oldVec, newVec)
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in
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(N0 (str, vec), NoAction)
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end
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else
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let val l2 = L2 (oldStr, oldVec, newStr, newVec)
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in (l2, AddedNode)
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end
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else
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(* Need to split in middle of string. *)
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let
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val sub1 = String.substring (oldStr, 0, curIdx)
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val sub2Len = String.size oldStr - curIdx
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val sub2 = String.substring (oldStr, curIdx, sub2Len)
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|
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val oldVecLen = Vector.length oldVec
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val midPoint = binSearch (String.size sub1, oldVec, 0, oldVecLen)
|
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|
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val newVecLen = Vector.length newVec
|
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in
|
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if
|
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isLessThanTarget (oldStr, newStr)
|
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isLessThanTarget (oldStr, newStr, oldVec, newVec)
|
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then
|
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(N0 (sub1 ^ newStr ^ sub2), NoAction)
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let
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val str = sub1 ^ newStr ^ sub2
|
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val totalVecLen = Vector.length oldVec + Vector.length newVec
|
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val vec = Vector.tabulate (totalVecLen, (fn idx =>
|
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if idx < midPoint then
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Vector.sub (oldVec, idx)
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else if idx < midPoint + newVecLen then
|
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Vector.sub (newVec, idx - midPoint)
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else
|
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Vector.sub (oldVec, idx - newVecLen)))
|
||||
in
|
||||
(N0 (str, vec), NoAction)
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||||
end
|
||||
else if
|
||||
curIdx + String.size newStr <= targetLength
|
||||
andalso midPoint + newVecLen <= targetVecLength
|
||||
then
|
||||
(L2 (sub1 ^ newStr, sub2), AddedNode)
|
||||
let
|
||||
val str1 = sub1 ^ newStr
|
||||
val vec1 = Vector.tabulate (midPoint + newVecLen, (fn idx =>
|
||||
if idx < midPoint then Vector.sub (oldVec, idx)
|
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else Vector.sub (newVec, idx - midPoint)))
|
||||
|
||||
val vec2 = Vector.tabulate (oldVecLen - midPoint, (fn idx =>
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Vector.sub (oldVec, idx + midPoint)))
|
||||
|
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val l2 = L2 (str1, vec1, sub2, vec2)
|
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in
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||||
(l2, AddedNode)
|
||||
end
|
||||
else if
|
||||
((String.size oldStr) - curIdx) + String.size newStr <= targetLength
|
||||
andalso (midPoint - oldVecLen) + newVecLen <= targetVecLength
|
||||
then
|
||||
(L2 (sub1, newStr ^ sub2), AddedNode)
|
||||
else
|
||||
(N3 (N0 sub1, N0 newStr, N0 sub2), AddedNode)
|
||||
end
|
||||
|
||||
fun ins (curIdx, newStr, rope) =
|
||||
case rope of
|
||||
N2 (l, lm, r) =>
|
||||
if curIdx < lm then
|
||||
let
|
||||
val (l, action) = ins (curIdx, newStr, l)
|
||||
val str2 = newStr ^ sub2
|
||||
val newStrLen = String.size newStr
|
||||
val vec2 =
|
||||
Vector.tabulate ((midPoint - oldVecLen) + newVecLen, (fn idx =>
|
||||
if idx < newVecLen then Vector.sub (newVec, idx)
|
||||
else Vector.sub (oldVec, idx - newVecLen) + newStrLen))
|
||||
|
||||
val vec1 = Vector.tabulate (midPoint, (fn idx =>
|
||||
Vector.sub (oldVec, idx)))
|
||||
|
||||
val l2 = L2 (sub1, vec1, str2, vec2)
|
||||
in
|
||||
(case action of
|
||||
NoAction =>
|
||||
(case (l, r) of
|
||||
(N0 s1, N0 s2) =>
|
||||
if isLessThanTarget (s1, s2) then
|
||||
(N0 (s1 ^ s2), DeletedNode)
|
||||
else
|
||||
(N2 (l, lm + String.size newStr, r), action)
|
||||
| _ => (N2 (l, lm + String.size newStr, r), action))
|
||||
| AddedNode => (insN2Left (l, r), action)
|
||||
| DeletedNode => (delN2Left (l, r), action))
|
||||
(l2, AddedNode)
|
||||
end
|
||||
else
|
||||
let
|
||||
val (r, action) = ins (curIdx - lm, newStr, r)
|
||||
val vec1 =
|
||||
if oldVecLen = 0 then
|
||||
emptyVec
|
||||
else
|
||||
Vector.tabulate (midPoint, (fn idx => Vector.sub (oldVec, idx)))
|
||||
|
||||
val vec2 =
|
||||
if oldVecLen = 0 orelse midPoint >= oldVecLen then
|
||||
emptyVec
|
||||
else
|
||||
Vector.tabulate (oldVecLen - midPoint, (fn idx =>
|
||||
Vector.sub (oldVec, midPoint + idx)))
|
||||
|
||||
val left = N0 (sub1, vec1)
|
||||
val right = N0 (sub2, vec2)
|
||||
val mid = N0 (newStr, newVec)
|
||||
in
|
||||
(case action of
|
||||
NoAction =>
|
||||
(case (l, r) of
|
||||
(N0 s1, N0 s2) =>
|
||||
if isLessThanTarget (s1, s2) then
|
||||
(N0 (s1 ^ s2), DeletedNode)
|
||||
else
|
||||
(N2 (l, lm, r), action)
|
||||
| _ => (N2 (l, lm, r), action))
|
||||
| AddedNode => (insN2Right (l, r), action)
|
||||
| DeletedNode => (delN2Right (l, r), action))
|
||||
(N3 (left, right, mid), AddedNode)
|
||||
end
|
||||
| N1 t =>
|
||||
let
|
||||
val (t, action) = ins (curIdx, newStr, t)
|
||||
in
|
||||
(case action of
|
||||
AddedNode => (insN1 t, action)
|
||||
| _ => (N1 t, action))
|
||||
end
|
||||
| N0 oldStr => insLeaf (curIdx, newStr, rope, oldStr)
|
||||
| _ => raise AuxConstructor
|
||||
|
||||
fun insert (index, str, rope) =
|
||||
let
|
||||
val (rope, action) = ins (index, str, rope)
|
||||
in
|
||||
(case action of
|
||||
NoAction => rope
|
||||
| AddedNode => insRoot rope
|
||||
| DeletedNode => delRoot rope)
|
||||
end
|
||||
|
||||
fun app (newStr, rope) =
|
||||
case rope of
|
||||
N2 (l, lm, r) =>
|
||||
let
|
||||
val (r, action) = app (newStr, r)
|
||||
in
|
||||
(case action of
|
||||
NoAction =>
|
||||
(case (l, r) of
|
||||
(N0 s1, N0 s2) =>
|
||||
if isLessThanTarget (s1, s2) then
|
||||
(N0 (s1 ^ s2), DeletedNode)
|
||||
else
|
||||
(N2 (l, lm, r), action)
|
||||
| _ => (N2 (l, lm, r), action))
|
||||
| AddedNode => (insN2Right (l, r), action)
|
||||
| DeletedNode => (delN2Right (l, r), action))
|
||||
end
|
||||
| N1 t =>
|
||||
let
|
||||
val (t, action) = app (newStr, t)
|
||||
in
|
||||
(case action of
|
||||
AddedNode => (insN1 t, action)
|
||||
| _ => (N1 t, action))
|
||||
end
|
||||
| N0 oldStr =>
|
||||
if isLessThanTarget (oldStr, newStr) then
|
||||
(N0 (oldStr ^ newStr), NoAction)
|
||||
else
|
||||
(L2 (oldStr, newStr), AddedNode)
|
||||
| _ => raise AuxConstructor
|
||||
|
||||
fun append (str, rope) =
|
||||
let
|
||||
val (rope, action) = app (str, rope)
|
||||
in
|
||||
(case action of
|
||||
NoAction => rope
|
||||
| AddedNode => insRoot rope
|
||||
| DeletedNode => delRoot rope)
|
||||
end
|
||||
|
||||
fun delLeaf (startIdx, endIdx, str) =
|
||||
if startIdx <= 0 andalso endIdx >= String.size str then
|
||||
(empty, false)
|
||||
else if startIdx >= 0 andalso endIdx <= String.size str then
|
||||
let
|
||||
val sub1 = String.substring (str, 0, startIdx)
|
||||
val sub2 = String.substring (str, endIdx, (String.size str - endIdx))
|
||||
in
|
||||
if isLessThanTarget (sub1, sub2) then (N0 (sub1 ^ sub2), false)
|
||||
else (L2 (sub1, sub2), true)
|
||||
end
|
||||
else if startIdx >= 0 andalso endIdx >= String.size str then
|
||||
let
|
||||
val start = Int.toString startIdx
|
||||
val str = String.substring (str, 0, startIdx)
|
||||
in
|
||||
(N0 str, false)
|
||||
end
|
||||
else
|
||||
let val str = String.substring (str, endIdx, String.size str - endIdx)
|
||||
in (N0 str, false)
|
||||
end
|
||||
|
||||
fun del (startIdx, endIdx, rope) =
|
||||
case rope of
|
||||
N2 (l, lm, r) =>
|
||||
if lm > startIdx andalso lm > endIdx then
|
||||
let
|
||||
val (l, didAdd) = del (startIdx, endIdx, l)
|
||||
in
|
||||
if didAdd then (insN2Left (l, r), didAdd)
|
||||
else (N2 (l, size l, r), didAdd)
|
||||
end
|
||||
else if lm < startIdx andalso lm < endIdx then
|
||||
let
|
||||
val (r, didAdd) = del (startIdx - lm, endIdx - lm, r)
|
||||
in
|
||||
if didAdd then (insN2Right (l, r), didAdd)
|
||||
else (N2 (l, lm, r), didAdd)
|
||||
end
|
||||
else
|
||||
let
|
||||
val (r, didAddR) = del (startIdx - lm, endIdx - lm, r)
|
||||
val (l, didaddL) = del (startIdx, endIdx, l)
|
||||
in
|
||||
if didaddL then (insN2Left (l, r), didaddL)
|
||||
else if didAddR then (insN2Right (l, r), didAddR)
|
||||
else (N2 (l, size l, r), false)
|
||||
end
|
||||
| N1 t =>
|
||||
let val (t, didAdd) = del (startIdx, endIdx, t)
|
||||
in if didAdd then (insN1 t, didAdd) else (N1 t, didAdd)
|
||||
end
|
||||
| N0 str => delLeaf (startIdx, endIdx, str)
|
||||
| _ => raise AuxConstructor
|
||||
|
||||
fun delete (start, length, rope) =
|
||||
let val (rope, didAdd) = del (start, start + length, rope)
|
||||
in if didAdd then insRoot rope else delRoot rope
|
||||
end
|
||||
end
|
||||
|
||||
Reference in New Issue
Block a user