Task
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package zio
Submerges the error case of an Either into the ZIO.
Submerges the error case of an Either into the ZIO. The inverse
operation of IO.either.
Accesses the environment of the effect.
Accesses the environment of the effect.
val portNumber = effect.access(_.config.portNumber)
Effectfully accesses the environment of the effect.
Effectfully accesses the environment of the effect.
Uncurried version.
Uncurried version. Doesn't offer curried syntax and have worse type-inference characteristics, but guarantees no extra allocations of intermediate scalaz.zio.ZIO.BracketAcquire and scalaz.zio.ZIO.BracketRelease objects.
When this effect represents acquisition of a resource (for example,
opening a file, launching a thread, etc.), bracket can be used to ensure
the acquisition is not interrupted and the resource is always released.
When this effect represents acquisition of a resource (for example,
opening a file, launching a thread, etc.), bracket can be used to ensure
the acquisition is not interrupted and the resource is always released.
The function does two things:
1. Ensures this effect, which acquires the resource, will not be
interrupted. Of course, acquisition may fail for internal reasons (an
uncaught exception).
2. Ensures the release effect will not be interrupted, and will be
executed so long as this effect successfully acquires the resource.
In between acquisition and release of the resource, the use effect is
executed.
If the release effect fails, then the entire effect will fail even
if the use effect succeeds. If this fail-fast behavior is not desired,
errors produced by the release effect can be caught and ignored.
openFile("data.json").bracket(closeFile) { file => for { header <- readHeader(file) ... } yield result }
Uncurried version.
Uncurried version. Doesn't offer curried syntax and have worse type-inference characteristics, but guarantees no extra allocations of intermediate scalaz.zio.ZIO.BracketExitAcquire and scalaz.zio.ZIO.BracketExitRelease objects.
Acquires a resource, uses the resource, and then releases the resource.
Acquires a resource, uses the resource, and then releases the resource.
Neither the acquisition nor the release will be interrupted, and the
resource is guaranteed to be released, so long as the acquire effect
succeeds. If use fails, then after release, the returned effect will fail
with the same error.
Evaluate each effect in the structure from left to right, and collect the results.
Evaluate each effect in the structure from left to right, and collect
the results. For a parallel version, see collectAllPar.
Evaluate each effect in the structure in parallel, and collect the results.
Evaluate each effect in the structure in parallel, and collect
the results. For a sequential version, see collectAll.
Evaluate each effect in the structure in parallel, and collect the results.
Evaluate each effect in the structure in parallel, and collect
the results. For a sequential version, see collectAll.
Unlike foreachAllPar, this method will use at most n fibers.
Returns information about the current fiber, such as its fiber identity.
Returns information about the current fiber, such as its fiber identity.
Returns an effect that dies with the specified Throwable.
Returns an effect that dies with the specified Throwable.
This method can be used for terminating a fiber because a defect has been
detected in the code.
Returns an effect that dies with a java.lang.RuntimeException having the specified text message.
Returns an effect that dies with a java.lang.RuntimeException having the specified text message. This method can be used for terminating a fiber because a defect has been detected in the code.
Returns an effect from a scalaz.zio.Exit value.
Returns an effect from a scalaz.zio.Exit value.
Imports a synchronous effect into a pure ZIO value, translating any
throwables into a Throwable failure in the returned value.
Imports a synchronous effect into a pure ZIO value, translating any
throwables into a Throwable failure in the returned value.
def putStrLn(line: String): Task[Unit] = Task.effect(println(line))
Imports an asynchronous effect into a pure ZIO value.
Imports an asynchronous effect into a pure ZIO value. See effectAsyncMaybe for
the more expressive variant of this function that can return a value
synchronously.
Imports an asynchronous effect into a pure IO value.
Imports an asynchronous effect into a pure IO value. The effect has the
option of returning the value synchronously, which is useful in cases
where it cannot be determined if the effect is synchronous or asynchronous
until the effect is actually executed. The effect also has the option of
returning a canceler, which will be used by the runtime to cancel the
asynchronous effect if the fiber executing the effect is interrupted.
Imports an asynchronous effect into a pure ZIO value.
Imports an asynchronous effect into a pure ZIO value. This formulation is
necessary when the effect is itself expressed in terms of ZIO.
Imports an asynchronous effect into a pure ZIO value, possibly returning
the value synchronously.
Imports an asynchronous effect into a pure ZIO value, possibly returning
the value synchronously.
Imports a total synchronous effect into a pure ZIO value.
Imports a total synchronous effect into a pure ZIO value.
The effect must not throw any exceptions. If you wonder if the effect
throws exceptions, then do not use this method, use Task.effect,
IO.effect, or ZIO.effect.
val nanoTime: UIO[Long] = IO.effectTotal(System.nanoTime())
Imports a total synchronous effect into a pure ZIO value.
Imports a total synchronous effect into a pure ZIO value. This variant
of effectTotal lets the impure code use the platform capabilities.
The effect must not throw any exceptions. If you wonder if the effect throws exceptions, then do not use this method, use Task.effect, IO.effect, or ZIO.effect.
val nanoTime: UIO[Long] = IO.effectTotal(System.nanoTime())
Accesses the whole environment of the effect.
Accesses the whole environment of the effect.
Returns an effect that models failure with the specified error.
Returns an effect that models failure with the specified error.
The moral equivalent of throw for pure code.
Returns an effect that first executes the outer effect, and then executes the inner effect, returning the value from the inner effect, and effectively flattening a nested effect.
Returns an effect that first executes the outer effect, and then executes the inner effect, returning the value from the inner effect, and effectively flattening a nested effect.
Folds an Iterable[A] using an effectful function f, working sequentially.
Folds an Iterable[A] using an effectful function f, working sequentially.
Applies the function f to each element of the Iterable[A] and
returns the results in a new List[B].
Applies the function f to each element of the Iterable[A] and
returns the results in a new List[B].
For a parallel version of this method, see foreachPar.
Applies the function f to each element of the Iterable[A] in parallel,
and returns the results in a new List[B].
Applies the function f to each element of the Iterable[A] in parallel,
and returns the results in a new List[B].
For a sequential version of this method, see foreach.
Applies the function f to each element of the Iterable[A] in parallel,
and returns the results in a new List[B].
Applies the function f to each element of the Iterable[A] in parallel,
and returns the results in a new List[B].
Unlike foreachPar, this method will use at most up to n fibers.
Returns an effect that forks all of the specified values, and returns a composite fiber that produces a list of their results, in order.
Returns an effect that forks all of the specified values, and returns a composite fiber that produces a list of their results, in order.
Returns an effect that forks all of the specified values, and returns a composite fiber that produces unit.
Returns an effect that forks all of the specified values, and returns a composite fiber that produces unit. This version is faster than forkAll in cases where the results of the forked fibers are not needed.
Lifts an Either into a ZIO value.
Lifts an Either into a ZIO value.
Creates a ZIO value that represents the exit value of the specified
fiber.
Creates a ZIO value that represents the exit value of the specified
fiber.
Creates a ZIO value that represents the exit value of the specified
fiber.
Creates a ZIO value that represents the exit value of the specified
fiber.
Lifts a function R => A into a ZIO[R, Nothing, A].
Lifts a function R => A into a ZIO[R, Nothing, A].
Lifts an effectful function whose effect requires no environment into an effect that requires the input to the function.
Lifts an effectful function whose effect requires no environment into an effect that requires the input to the function.
Imports a function that creates a scala.concurrent.Future from an
scala.concurrent.ExecutionContext into a ZIO.
Imports a function that creates a scala.concurrent.Future from an
scala.concurrent.ExecutionContext into a ZIO.
Lifts a Try into a ZIO.
Lifts a Try into a ZIO.
Returns an effect that models failure with the specified Cause.
Returns an effect that models failure with the specified Cause.
Returns an effect that is interrupted.
Returns an effect that is interrupted.
Returns an effect that will execute the specified effect fully on the provided executor, before returning to the default executor.
Returns an effect that will execute the specified effect fully on the provided executor, before returning to the default executor.
Merges an Iterable[IO] to a single IO, working sequentially.
Merges an Iterable[IO] to a single IO, working sequentially.
Merges an Iterable[IO] to a single IO, working in parallel.
Merges an Iterable[IO] to a single IO, working in parallel.
Returns a effect that will never produce anything.
Returns a effect that will never produce anything. The moral
equivalent of while(true) {}, only without the wasted CPU cycles.
Given an environment R, returns a function that can supply the
environment to programs that require it, removing their need for any
specific environment.
Given an environment R, returns a function that can supply the
environment to programs that require it, removing their need for any
specific environment.
This is similar to dependency injection, and the provide function can be
thought of as inject.
Races an IO[E, A] against zero or more other effects.
Races an IO[E, A] against zero or more other effects. Yields either the
first success or the last failure.
Reduces an Iterable[IO] to a single IO, working sequentially.
Reduces an Iterable[IO] to a single IO, working sequentially.
Reduces an Iterable[IO] to a single IO, working in parallel.
Reduces an Iterable[IO] to a single IO, working in parallel.
Requires that the given IO[E, Option[A]] contain a value.
Requires that the given IO[E, Option[A]] contain a value. If there is no
value, then the specified error will be raised.
Returns an effect that accesses the runtime, which can be used to (unsafely) execute tasks.
Returns an effect that accesses the runtime, which can be used to (unsafely) execute tasks. This is useful for integration with non-functional code that must call back into functional code.
Returns an effect that models success with the specified strictly- evaluated value.
Returns an effect that models success with the specified strictly- evaluated value.
Returns an effect that models success with the specified lazily-evaluated value.
Returns an effect that models success with the specified lazily-evaluated
value. This method should not be used to capture effects. See
ZIO.effectTotal for capturing total effects, and ZIO.effect for capturing
partial effects.
Returns an effect that supervises the specified effect, ensuring that all fibers that it forks are interrupted as soon as the supervised effect completes.
Returns an effect that supervises the specified effect, ensuring that all fibers that it forks are interrupted as soon as the supervised effect completes.
Returns an effect that supervises the specified effect, ensuring that all fibers that it forks are passed to the specified supervisor as soon as the supervised effect completes.
Returns an effect that supervises the specified effect, ensuring that all fibers that it forks are passed to the specified supervisor as soon as the supervised effect completes.
Returns a lazily constructed effect, whose construction may itself require effects.
Returns a lazily constructed effect, whose construction may itself require
effects. This is a shortcut for flatten(effectTotal(io)).
Strictly-evaluated unit lifted into the ZIO monad.
Strictly-evaluated unit lifted into the ZIO monad.
The inverse operation IO.sandboxed
The inverse operation IO.sandboxed
Terminates with exceptions on the Left side of the Either error, if it
exists. Otherwise extracts the contained IO[E, A]
The moral equivalent of if (p) exp
The moral equivalent of if (p) exp
The moral equivalent of if (p) exp when p has side-effects
The moral equivalent of if (p) exp when p has side-effects
Returns an effect that yields to the runtime system, starting on a fresh stack.
Returns an effect that yields to the runtime system, starting on a fresh stack. Manual use of this method can improve fairness, at the cost of overhead.