Mojo Example that demos the difference between providing and requesting an interface

examples/indirect_service/README.md

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+Indirect Service Demo
+=====================
+
+This demo is intended to highlight the difference between requesting a service and providing one. The demo is based on two services: IntegerService and IndirectIntegerService.

[Aaron Boodman, 2014/11/20 07:21:58]

You should wrap at 80 cols.

[hansmuller, 2014/11/20 17:53:03]

Done.

+
+interface IntegerService {
+  Increment() => (int32 value);
+};
+
+This trival interface just manages a single internal integer that's initialized to 0. The Increment() method returns the old value.

[Aaron Boodman, 2014/11/20 07:21:58]

It doesn't seem the term 'old' is meaningful with this interface. It always
returns a new integer right? How would a client know whether it was pre or post
increment.

[hansmuller, 2014/11/20 17:53:04]

Done.

+
+interface IndirectIntegerService {
+    Set(IntegerService? service);
+    Get(IntegerService&? service);
+};
+
+This service delegates to the one IntegerService provided by the Set() method. Clients use Get() to request a connection to an IntegerService targets the delegate. This is roughly an IntegerService "pointer".

[Aaron Boodman, 2014/11/20 07:21:58]

s/targets/targetting/

[hansmuller, 2014/11/20 17:53:04]

Done.

+
+The demo creates a set of threads all of which get their own connection to the shared IntegerService via the IndirectIntegerService. The threads all access the IntegerService at the same time and then display a little table of the results.
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