Scala：Parvector不符合上限[_] =＆gt;＆gt; seq [？]

发布于 2025-02-13 09:58:28 字数 850 浏览 0 评论 0原文

我正在使用平行集合模块，版本1.0.4（ github ）。我有以下类型定义定义矩阵的通用版本的定义：

type Matrix[T, C[_] <: Seq[_]] = C[C[T]]

正如预期的那样，使用向量作为集合类型时初始化此类矩阵有效：

val vecMatrix: Matrix[Double, Vector] = 
  Vector(Vector(0.5, 0.6), Vector(0.6, 0.8))

但是，使用Parvector会产生编译器错误：

val parvecMatrix: Matrix[Double, ParVector] =
  ParVector(ParVector(0.5, 0.6), ParVector(0.6, 0.8))

类型参数collection.parallel.immutable.parvector不符合上限[_] =＆gt;＆gt; seq [？]

我读这本书是因为Parvector不是Seq的子类型。但是，scala.collection.parallel.parseqlike的文档，Parvector的线性超级画作，明确指出：

并行序列继承seq特征。

文档错误吗？还是我的代码有一个问题可以防止上部界限？

原文

I am using Scala 3.1.3 with the parallel collections module, version 1.0.4 (Github).
I have the following type definition defining a generic version of a matrix:

type Matrix[T, C[_] <: Seq[_]] = C[C[T]]

As expected, initializing such a matrix works when using Vector as the collection type:

val vecMatrix: Matrix[Double, Vector] = 
  Vector(Vector(0.5, 0.6), Vector(0.6, 0.8))

However, using ParVector instead yields a compiler error:

val parvecMatrix: Matrix[Double, ParVector] =
  ParVector(ParVector(0.5, 0.6), ParVector(0.6, 0.8))

Type argument collection.parallel.immutable.ParVector does not conform to upper bound [_] =>> Seq[?]

I read this as meaning ParVector is not a subtype of Seq. However, the documentation of scala.collection.parallel.ParSeqLike, a linear supertrait of ParVector, explicitly states: