Questions tagged [specialized-annotation]
14 questions
43
votes
3 answers
Why are so few things @specialized in Scala's standard library?
I've searched for the use of @specialized in the source code of the standard library of Scala 2.8.1. It looks like only a handful of traits and classes use this annotation: Function0, Function1, Function2, Tuple1, Tuple2, Product1, Product2,…
Jesper
- 202,709
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30
votes
4 answers
Specialization of generic functions in Scala (or Java)
Is it possible to specialize generic functions (or class) in Scala? For example, I want to write a generic function that writes data into a ByteBuffer:
def writeData[T](buffer: ByteBuffer, data: T) = buffer.put(data)
But as the put method takes…
K J
- 4,505
- 6
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12
votes
1 answer
Implementing a fixed size, immutable, and specialized vector
For performance and safety I would like to implement a fixed-size vector which is both immutable and specialized (I need fast arithmetics). My first idea was to use the @specialized annotation (because I need both integers and reals).
Here is a…
paradigmatic
- 40,153
- 18
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4
votes
0 answers
Is it possible to obtain the effect of a specialized value class in scala?
I know how @specialized classes and value classes work and I know that I can't have a specialized value class as in:
class MilliVolt[@specialized T](val content :T) extends AnyVal //illegal
I can't find a way to obtain a similiar effect: with a…
Turin
- 2,208
- 15
- 23
3
votes
1 answer
Pattern matching with specialized in Scala
I have a class that must work with Double and Float. I use generic with @specialized annotation for (Double, Float) due to performance requirements. There are two third-party functions, that I need to call. ffunc(x: Float) accepts Float, dfunc(y:…
Alexander
- 847
- 1
- 9
- 18
2
votes
1 answer
Scala @specialized annotation infinite recursion?
Version: scala 2.11.8
I defined a class with specialized type and override method in inheritance:
class Father[@specialized(Int) A]{
def get(from: A): A = from
}
class Son extends Father[Int]{
override def get(from: Int): Int = {
…
Jiang Yukun
- 73
- 3
2
votes
1 answer
@specialized + inner classes not allowed in scala?
When I compile the following:
import org.junit.Test
class TypesTest{
@Test
def specializedTest(): Unit = {
trait TTBase[@specialized T] {
def evaluate:T
}
case class TTX[@specialized T](value:T) extends TTBase[T] {
…
user48956
- 14,850
- 19
- 93
- 154
2
votes
0 answers
Scala @specialized annotation on function doesn't generate specialized type in pattern matching
I have the following function in scala, I intend to use it to convert any traversable into array and wrap any non-traversable with array:
def asArray[@specialized(scala.Int, scala.Long, scala.Float, scala.Double/*, scala.AnyRef*/) T <: Any :…
tribbloid
- 4,026
- 14
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- 103
2
votes
2 answers
scala specialized general numeric operations
I want a class that encapsulates both integral and floating point numbers.
Basically I want to be able to do something like this
Const(5) + Const(6) = Const(11)
Const(5) + Const(6.0) = Const(11.0)
The code with compiler errors.
case class…
smartnut007
- 6,324
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2
votes
2 answers
How to obtain the raw datatype of a parameter of a field that is specialized in Scala via reflection?
I have a class with a field that is specialized and is using a raw datatype. For instance a Tuple2[Int, String]:
scala> class TupleReflection(val tuple: Tuple2[Int, String])
defined class TupleReflection
scala> val refl = new TupleReflection((5,…
Tomas Lazaro
- 315
- 1
- 8
1
vote
0 answers
Methods in trait are not getting specialized
Let the following setup:
sealed trait Test[@specialized T] {
implicit protected def tag: ClassTag[T]
def xs: Array[T]
def count(condition: T => Boolean): Int = {
@tailrec
def innerLoop(index: Int, acc: Int): Int =
if (index ==…
sanyi14ka
- 809
- 9
- 14
1
vote
0 answers
Benefit for @specialized in template base where template parameter known at call?
Suppose I have:
trait Normalizer[T]{
def apply(x:T):T
}
case class DoubleNormalizer() extends Normalizer[Double] {
def apply(x:Double):Double {
... impl ...
}
}
Does boxing/unboxing happen in either of the following cases, and would…
user48956
- 14,850
- 19
- 93
- 154
0
votes
1 answer
Proper work to specialize generic classes in Python
I am having a hard time using python typing annotations when dealing with generics and compound types
Consider the following class:
import typing as ty
T = ty.TypeVar("T")
CT = tuple[bool, T, str]
class MyClass(ty.Generic[T]):
internal1:…
Hernan
- 5,811
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0
votes
1 answer
Why can't I specialize a generic function in scala?
I get an error saying type N is unused or used in non-specializable positions., for the method with the following signature:
protected def offsetFrom0[@specialized(Int,Long) N](offsetFrom1 : Codec[N])(implicit N : Integral[N]) : Codec[N]
Can…
Luciano
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