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# futures

This is a simple example of defining and using _futures_, a common concurrent
programming idiom. A future is used to represent a term that may not yet be
available due to a pending asynchronous computation. Futures are supported
in Logtalk using its high-level multi-threading features. This example uses
computations over lists as representative of long running operations that
would benefit from asynchronous calls.

Start by loading the example:

```logtalk
logtalk_load(futures(loader)).
```

Use the asynchronous calls based predicate definition:

```logtalk
integer::sequence(1,100,List1), integer::sequence(101,200,List2), list_math::product_sum(List1,List2,Result).
```

<!--
Result = 76002500.
-->

Use the threaded engines based predicate definition:

```logtalk
integer::sequence(1,100,List1), integer::sequence(101,200,List2), list_math::product_sum_engines(List1,List2,Result).
```

<!--
Result = 76002500.
-->
