txt: ## dist_cpan-SAMGWISE-Seq-PreFetch.md
  # NAME
  
  Seq::PreFetch - Asynchronously pre-fetch the next item of a Seq
  
  # SYNOPSIS
  
  ```
  use Seq::PreFetch;
  
  sub slow-and-lazy( --> Seq) {
    gather for 1..* {
      # a time expensive option... like sleep
      sleep 0.5;
      .take
    }
  }
  
  my $moment = now;
  for slow-and-lazy.&pre-fetch {
    .say;
    say "Delta: { now - $moment }";
    $moment = now;
    sleep 1;
  }
  
  ```
  
  # DESCRIPTION
  
  Seq::PreFetch asynchronously pre-fetches the next item of a Seq before you pull from the Seq. It provides the sub pre-fetch which wraps a Seq with a pre-fetching Seq.
  
  This pattern allows you to consume one value from a Seq and begin concurrently calculating the next value of a Seq ready for the next time you need a value. Time efficiency gains can be made for operations where the time cost of a consuming loop is greater than the cost of starting a thread to pre-fetch.
  
  As demonstrated in the synopsis example, The two operations do not block so the longer sleep in the loop defines the duration after the first iteration.
  
  # AUTHOR
  
  Sam Gillespie [samgwise@gmail.com](mailto:samgwise@gmail.com)
  
  # COPYRIGHT AND LICENSE
  
  Copyright 2017 Sam Gillespie
  
  This library is free software; you can redistribute it and/or modify it under the Artistic License 2.0.
  