35 lines
845 B
Markdown
35 lines
845 B
Markdown
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# lazySource
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Defers creation and materialization of a `Source` until there is demand.
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@ref[Source operators](../index.md#source-operators)
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@@@div { .group-scala }
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## Signature
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@@signature [Source.scala](/akka-stream/src/main/scala/akka/stream/scaladsl/Source.scala) { #lazySource }
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@@@
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## Description
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Defers creation and materialization of a `Source` until there is demand, then emits the elements from the source
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downstream just like if it had been created up front.
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See also @ref:[lazyFutureSource](lazyFutureSource.md).
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Note that asynchronous boundaries (and other operators) in the stream may do pre-fetching which counter acts
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the laziness and will trigger the factory immediately.
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## Reactive Streams semantics
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@@@div { .callout }
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**emits** depends on the wrapped `Source`
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**completes** depends on the wrapped `Source`
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@@@
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