package dotty.tools.dotc.util
import collection.mutable.ListBuffer
abstract class SimpleMap[K <: AnyRef, +V >: Null <: AnyRef] extends (K => V) {
def size: Int
def apply(k: K): V
def remove(k: K): SimpleMap[K, V]
def updated[V1 >: V <: AnyRef](k: K, v: V1): SimpleMap[K, V1]
def contains(k: K): Boolean = apply(k) != null
def mapValues[V1 >: V <: AnyRef](f: (K, V1) => V1): SimpleMap[K, V1]
def foreachBinding(f: (K, V) => Unit): Unit
def map2[T](f: (K, V) => T): List[T] = {
val buf = new ListBuffer[T]
foreachBinding((k, v) => buf += f(k, v))
buf.toList
}
def keys: List[K] = map2((k, v) => k)
def toList: List[(K, V)] = map2((k, v) => (k, v))
override def toString = {
def assocToString(key: K, value: V) = s"$key -> $value"
map2(assocToString) mkString ("(", ", ", ")")
}
}
object SimpleMap {
private val CompactifyThreshold = 4
private object myEmpty extends SimpleMap[AnyRef, Null] {
def size = 0
def apply(k: AnyRef) = null
def remove(k: AnyRef) = this
def updated[V1 >: Null <: AnyRef](k: AnyRef, v: V1) = new Map1(k, v)
def mapValues[V1 >: Null <: AnyRef](f: (AnyRef, V1) => V1) = this
def foreachBinding(f: (AnyRef, Null) => Unit) = ()
}
def Empty[K <: AnyRef] = myEmpty.asInstanceOf[SimpleMap[K, Null]]
class Map1[K <: AnyRef, +V >: Null <: AnyRef] (k1: K, v1: V) extends SimpleMap[K, V] {
def size = 1
def apply(k: K) =
if (k == k1) v1
else null
def remove(k: K) =
if (k == k1) Empty.asInstanceOf[SimpleMap[K, V]]
else this
def updated[V1 >: V <: AnyRef](k: K, v: V1) =
if (k == k1) new Map1(k, v)
else new Map2(k1, v1, k, v)
def mapValues[V1 >: V <: AnyRef](f: (K, V1) => V1) = {
val w1 = f(k1, v1)
if (v1 eq w1) this else new Map1(k1, w1)
}
def foreachBinding(f: (K, V) => Unit) = f(k1, v1)
}
class Map2[K <: AnyRef, +V >: Null <: AnyRef] (k1: K, v1: V, k2: K, v2: V) extends SimpleMap[K, V] {
def size = 2
def apply(k: K) =
if (k == k1) v1
else if (k == k2) v2
else null
def remove(k: K) =
if (k == k1) new Map1(k2, v2)
else if (k == k2) new Map1(k1, v1)
else this
def updated[V1 >: V <: AnyRef](k: K, v: V1) =
if (k == k1) new Map2(k, v, k2, v2)
else if (k == k2) new Map2(k1, v1, k, v)
else new Map3(k1, v1, k2, v2, k, v)
def mapValues[V1 >: V <: AnyRef](f: (K, V1) => V1) = {
val w1 = f(k1, v1); val w2 = f(k2, v2)
if ((v1 eq w1) && (v2 eq w2)) this
else new Map2(k1, w1, k2, w2)
}
def foreachBinding(f: (K, V) => Unit) = { f(k1, v1); f(k2, v2) }
}
class Map3[K <: AnyRef, +V >: Null <: AnyRef] (k1: K, v1: V, k2: K, v2: V, k3: K, v3: V) extends SimpleMap[K, V] {
def size = 3
def apply(k: K) =
if (k == k1) v1
else if (k == k2) v2
else if (k == k3) v3
else null
def remove(k: K) =
if (k == k1) new Map2(k2, v2, k3, v3)
else if (k == k2) new Map2(k1, v1, k3, v3)
else if (k == k3) new Map2(k1, v1, k2, v2)
else this
def updated[V1 >: V <: AnyRef](k: K, v: V1) =
if (k == k1) new Map3(k, v, k2, v2, k3, v3)
else if (k == k2) new Map3(k1, v1, k, v, k3, v3)
else if (k == k3) new Map3(k1, v1, k2, v2, k, v)
else new Map4(k1, v1, k2, v2, k3, v3, k, v)
def mapValues[V1 >: V <: AnyRef](f: (K, V1) => V1) = {
val w1 = f(k1, v1); val w2 = f(k2, v2); val w3 = f(k3, v3)
if ((v1 eq w1) && (v2 eq w2) && (v3 eq w3)) this
else new Map3(k1, w1, k2, w2, k3, w3)
}
def foreachBinding(f: (K, V) => Unit) = { f(k1, v1); f(k2, v2); f(k3, v3) }
}
class Map4[K <: AnyRef, +V >: Null <: AnyRef] (k1: K, v1: V, k2: K, v2: V, k3: K, v3: V, k4: K, v4: V) extends SimpleMap[K, V] {
def size = 4
def apply(k: K) =
if (k == k1) v1
else if (k == k2) v2
else if (k == k3) v3
else if (k == k4) v4
else null
def remove(k: K) =
if (k == k1) new Map3(k2, v2, k3, v3, k4, v4)
else if (k == k2) new Map3(k1, v1, k3, v3, k4, v4)
else if (k == k3) new Map3(k1, v1, k2, v2, k4, v4)
else if (k == k4) new Map3(k1, v1, k2, v2, k3, v3)
else this
def updated[V1 >: V <: AnyRef](k: K, v: V1) =
if (k == k1) new Map4(k, v, k2, v2, k3, v3, k4, v4)
else if (k == k2) new Map4(k1, v1, k, v, k3, v3, k4, v4)
else if (k == k3) new Map4(k1, v1, k2, v2, k, v, k4, v4)
else if (k == k4) new Map4(k1, v1, k2, v2, k3, v3, k, v)
else new MapMore(Array[AnyRef](k1, v1, k2, v2, k3, v3, k4, v4, k, v))
def mapValues[V1 >: V <: AnyRef](f: (K, V1) => V1) = {
val w1 = f(k1, v1); val w2 = f(k2, v2); val w3 = f(k3, v3); val w4 = f(k4, v4)
if ((v1 eq w1) && (v2 eq w2) && (v3 eq w3) && (v4 eq w4)) this
else new Map4(k1, w1, k2, w2, k3, w3, k4, w4)
}
def foreachBinding(f: (K, V) => Unit) = { f(k1, v1); f(k2, v2); f(k3, v3); f(k4, v4) }
}
class MapMore[K <: AnyRef, +V >: Null <: AnyRef](bindings: Array[AnyRef]) extends SimpleMap[K, V] {
private def key(i: Int): K = bindings(i).asInstanceOf[K]
private def value(i: Int): V = bindings(i + 1).asInstanceOf[V]
def size = bindings.length / 2
def apply(k: K): V = {
var i = 0
while (i < bindings.length) {
if (bindings(i) eq k) return value(i)
i += 2
}
null
}
def remove(k: K): SimpleMap[K, V] = {
var i = 0
while (i < bindings.length) {
if (bindings(i) eq k) return {
if (size == CompactifyThreshold) {
var m: SimpleMap[K, V] = Empty[K]
for (j <- 0 until bindings.length by 2)
if (j != i) m = m.updated(key(j), value(j))
m
} else {
val bindings1 = new Array[AnyRef](bindings.length - 2)
Array.copy(bindings, 0, bindings1, 0, i)
Array.copy(bindings, i + 2, bindings1, i, bindings1.length - i)
new MapMore(bindings1)
}
}
i += 2
}
this
}
def updated[V1 >: V <: AnyRef](k: K, v: V1): SimpleMap[K, V] = {
var i = 0
while (i < bindings.length) {
if (bindings(i) eq k)
return {
if (v eq bindings(i + 1)) this
else {
val bindings1 = bindings.clone.asInstanceOf[Array[AnyRef]]
bindings1(i + 1) = v
new MapMore(bindings1)
}
}
i += 2
}
val bindings2 = new Array[AnyRef](bindings.length + 2)
Array.copy(bindings, 0, bindings2, 0, bindings.length)
bindings2(bindings.length) = k
bindings2(bindings.length + 1) = v
new MapMore(bindings2)
}
override def contains(k: K): Boolean = {
var i = 0
while (i < bindings.length) {
if (bindings(i) eq k) return true
i += 2
}
false
}
def mapValues[V1 >: V <: AnyRef](f: (K, V1) => V1) = {
var bindings1: Array[AnyRef] = bindings
var i = 0
while (i < bindings.length) {
val v = value(i)
val v1 = f(key(i), v)
if ((v1 ne v) && (bindings1 eq bindings))
bindings1 = bindings.clone.asInstanceOf[Array[AnyRef]]
bindings1(i) = bindings(i)
bindings1(i + 1) = v1
i += 2
}
if (bindings1 eq bindings) this else new MapMore(bindings1)
}
def foreachBinding(f: (K, V) => Unit) = {
var i = 0
while (i < bindings.length) {
f(key(i), value(i))
i += 2
}
}
}
}