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lewisjkl/future-referential-transparency.scala

Last active January 5, 2020 13:53
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Expressions using Future are often not referentially transparent.
Raw
future-referential-transparency.scala
val printStuff: Future[Unit] = Future(println("Hello, World!"))
for {
_ <- printStuff
_ <- printStuff
} yield ()
// prints "Hello, World!" once
for {
_ <- Future(println("Hello, World!"))
_ <- Future(println("Hello, World!"))
} yield ()
// prints "Hello, World!" twice
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