Resource

Creates a resource from an allocating effect.

Type parameters:

A: the type of the resource
F: the effect type in which the resource is acquired and released

Value parameters:

resource: an effect that returns a tuple of a resource and an effect to release it

See also:

make for a version that separates the needed resource with its finalizer tuple in two parameters

Source:

Resource.scala

Creates a resource from an allocating effect, with a finalizer that is able to distinguish between exit cases.

Type parameters:

A: the type of the resource
F: the effect type in which the resource is acquired and released

Value parameters:

resource: an effect that returns a tuple of a resource and an effectful function to release it

See also:

makeCase for a version that separates the needed resource with its finalizer tuple in two parameters

Source:

Resource.scala

Creates a resource from an allocating effect, with a finalizer that is able to distinguish between exit cases.

The action takes a Poll[F] to allow for interruptible acquires, which is most often useful when acquiring lock-like structure: it should be possible to interrupt a fiber waiting on a lock, but if it does get acquired, release need to be guaranteed.

Note that in this case the acquire action should know how to cleanup after itself in case it gets canceled, since Resource will only guarantee release when acquire succeeds and fails (and when the actions in use or flatMap fail, succeed, or get canceled)

TODO make sure this api, which is more general than makeFull, doesn't allow for interruptible releases

Type parameters:

A: the type of the resource
F: the effect type in which the resource is acquired and released

Value parameters:

resource: an effect that returns a tuple of a resource and an effectful function to release it, where acquisition can potentially be interrupted

See also:

makeFull for a version that separates the needed resource with its finalizer tuple in two parameters

Source:

Resource.scala

Allocates two resources concurrently, and combines their results in a tuple.

Source:: Resource.scala

Source:: Resource.scala

Source:: Resource.scala

Source:: Resource.scala

Source:: Resource.scala

Lifts an applicative into a resource. The resource has a no-op release. Preserves interruptibility of fa.

Value parameters:

fa: the value to lift into a resource

Source:

Resource.scala

Source:: Resource.scala

Creates a Resource by wrapping a Java AutoCloseable.

In most real world cases, implementors of AutoCloseable are blocking as well, so the close action runs in the blocking context.

Type parameters:

A: the type of the autocloseable resource
F: the type of the effect

Value parameters:

F: the effect type in which the resource was acquired and will be released
acquire: The effect with the resource to acquire.

Returns:

a Resource that will automatically close after use

Example:

 import cats.effect._
 import scala.io.Source
 def reader(data: String): Resource[IO, Source] =
   Resource.fromAutoCloseable(IO.blocking {
     Source.fromString(data)
   })

 import cats.effect._
 import scala.io.Source
 def reader[F[_]](data: String)(implicit F: Sync[F]): Resource[F, Source] =
   Resource.fromAutoCloseable(F.blocking {
     Source.fromString(data)
   })

Source:

Resource.scala

Lifts an applicative into a resource as a FunctionK. The resource has a no-op release.

Source:: Resource.scala

Creates a resource from an acquiring effect and a release function.

Type parameters:

A: the type of the resource
F: the effect type in which the resource is acquired and released

Value parameters:

acquire: an effect to acquire a resource
release: a function to effectfully release the resource returned by acquire

Source:

Resource.scala

Creates a resource from an acquiring effect and a release function that can discriminate between different exit cases.

Type parameters:

A: the type of the resource
F: the effect type in which the resource is acquired and released

Value parameters:

acquire: a function to effectfully acquire a resource
release: a function to effectfully release the resource returned by acquire

Source:

Resource.scala

Creates a resource from an acquiring effect and a release function that can discriminate between different exit cases.

The acquiring effect takes a Poll[F] to allow for interruptible acquires, which is most often useful when acquiring lock-like structures: it should be possible to interrupt a fiber waiting on a lock, but if it does get acquired, release need to be guaranteed.

Note that in this case the acquire action should know how to cleanup after itself in case it gets canceled, since Resource will only guarantee release when acquire succeeds and fails (and when the actions in use or flatMap fail, succeed, or get canceled)

Type parameters:

A: the type of the resource
F: the effect type in which the resource is acquired and released

Value parameters:

acquire: an effect to acquire a resource, possibly interruptibly
release: a function to effectfully release the resource returned by acquire

Source:

Resource.scala

Creates a resource from an acquiring effect and a release function that can discriminate between different exit cases.

The acquiring effect takes a Poll[F] to allow for interruptible acquires, which is most often useful when acquiring lock-like structures: it should be possible to interrupt a fiber waiting on a lock, but if it does get acquired, release need to be guaranteed.

Note that in this case the acquire action should know how to cleanup after itself in case it gets canceled, since Resource will only guarantee release when acquire succeeds and fails (and when the actions in use or flatMap fail, succeed, or get canceled)

Type parameters: