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NAME

Future::AsyncAwait::Hooks - scoped hook blocks that run extra code around await expressions

SYNOPSIS

   use Future::AsyncAwait;
   use Future::AsyncAwait::Hooks;

   async sub do_work
   {
      suspend { say "do_work is pausing here" }
      resume  { say "do_Work has woken up again" }

      my $result = (await inner_1()) + (await inner_2());
      return $result;
   }

DESCRIPTION

This module provides two extra syntax keywords for inserting code that can observe the suspend and resume behaviour of await expressions within an async sub.

These two keywords are lexically scoped. They affect await expressions later within their own scope, or scopes nested within it. They do not affect any await expressions in scopes outside of those in which they appear.

KEYWORDS

suspend

   async sub {
      suspend { BLOCK }
   }

Inserts a block of code to run every time a subsequent await expression at this block level pauses execution of the async sub.

resume

   async sub {
      resume { BLOCK }
   }

Inserts a block of code to run every time a subsequent await expression at this block level resumes execution of the async sub after a pause.

TODO

  • Maybe work out why it doesn't appear to work on perls older than 5.24. Or maybe nobody will be writing new code and needs it back that old?

AUTHOR

Paul Evans <leonerd@leonerd.org.uk>