CompileOps
Related Doc:
package Stream
Compiles this stream in to a value of the target effect type F and
discards any output values of the stream.
Compiles this stream in to a value of the target effect type F by folding
the output values together, starting with the provided init and combining the
current value with each output value.
Compiles this stream in to a value of the target effect type F by folding
the output chunks together, starting with the provided init and combining the
current value with each output chunk.
Compiles this stream in to a value of the target effect type F by folding
the output chunks together, starting with the provided init and combining the
current value with each output chunk.
When this method has returned, the stream has not begun execution -- this method simply compiles the stream down to the target effect type.
Like fold but uses the implicitly available Monoid[O] to combine elements.
Like fold but uses the implicitly available Monoid[O] to combine elements.
scala> import cats.implicits._, cats.effect.IO scala> Stream(1, 2, 3, 4, 5).covary[IO].compile.foldMonoid.unsafeRunSync res0: Int = 15
Like fold but uses the implicitly available Semigroup[O] to combine elements.
Like fold but uses the implicitly available Semigroup[O] to combine elements.
If the stream emits no elements, None is returned.
scala> import cats.implicits._, cats.effect.IO scala> Stream(1, 2, 3, 4, 5).covary[IO].compile.foldSemigroup.unsafeRunSync res0: Option[Int] = Some(15) scala> Stream.empty.covaryAll[IO, Int].compile.foldSemigroup.unsafeRunSync res1: Option[Int] = None
Compiles this stream in to a value of the target effect type F,
returning None if the stream emitted no values and returning the
last value emitted wrapped in Some if values were emitted.
Compiles this stream in to a value of the target effect type F,
returning None if the stream emitted no values and returning the
last value emitted wrapped in Some if values were emitted.
When this method has returned, the stream has not begun execution -- this method simply compiles the stream down to the target effect type.
scala> import cats.effect.IO scala> Stream.range(0,100).take(5).covary[IO].compile.last.unsafeRunSync res0: Option[Int] = Some(4)
Compiles this stream in to a value of the target effect type F,
raising a NoSuchElementException if the stream emitted no values
and returning the last value emitted otherwise.
Compiles this stream in to a value of the target effect type F,
raising a NoSuchElementException if the stream emitted no values
and returning the last value emitted otherwise.
When this method has returned, the stream has not begun execution -- this method simply compiles the stream down to the target effect type.
scala> import cats.effect.IO scala> Stream.range(0,100).take(5).covary[IO].compile.lastOrError.unsafeRunSync res0: Int = 4 scala> Stream.empty.covaryAll[IO, Int].compile.lastOrError.attempt.unsafeRunSync res1: Either[Throwable, Int] = Left(java.util.NoSuchElementException)
Compiles this stream into a value of the target effect type F by logging
the output values to a C, given a CanBuildFrom.
Compiles this stream into a value of the target effect type F by logging
the output values to a C, given a CanBuildFrom.
When this method has returned, the stream has not begun execution -- this method simply compiles the stream down to the target effect type.
scala> import cats.effect.IO scala> Stream.range(0,100).take(5).covary[IO].compile.to[List].unsafeRunSync res0: List[Int] = List(0, 1, 2, 3, 4)
Compiles this stream in to a value of the target effect type F by logging
the output values to a Chunk.
Compiles this stream in to a value of the target effect type F by logging
the output values to a Chunk.
When this method has returned, the stream has not begun execution -- this method simply compiles the stream down to the target effect type.
scala> import cats.effect.IO scala> Stream.range(0,100).take(5).covary[IO].compile.toChunk.unsafeRunSync res0: Chunk[Int] = Chunk(0, 1, 2, 3, 4)
Compiles this stream in to a value of the target effect type F by logging
the output values to a List.
Compiles this stream in to a value of the target effect type F by logging
the output values to a List. Equivalent to to[List].
When this method has returned, the stream has not begun execution -- this method simply compiles the stream down to the target effect type.
scala> import cats.effect.IO scala> Stream.range(0,100).take(5).covary[IO].compile.toList.unsafeRunSync res0: List[Int] = List(0, 1, 2, 3, 4)
Compiles this stream in to a value of the target effect type F by logging
the output values to a Vector.
Compiles this stream in to a value of the target effect type F by logging
the output values to a Vector. Equivalent to to[Vector].
When this method has returned, the stream has not begun execution -- this method simply compiles the stream down to the target effect type.
scala> import cats.effect.IO scala> Stream.range(0,100).take(5).covary[IO].compile.toVector.unsafeRunSync res0: Vector[Int] = Vector(0, 1, 2, 3, 4)
Projection of a
Streamproviding various ways to compile aStream[F,O]to anF[...].