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# self_vs_this

This example illustrates the differences between *self* and *this* and
also the execution-context built-in methods that allow to access the
values of *self*, *this*, and *sender*.

For an in-depth discussion of these concepts, see the corresponding
Handbook glossary entries, the section on "Predicates", and the
reference pages on the the execution-context built-in methods.

For an additional example using parametric objects, see the `sicstus`
example.

Print Logtalk, Prolog backend, and kernel versions (if running as a notebook):

```logtalk
%versions
```

Start by loading the example:

```logtalk
logtalk_load(self_vs_this(loader)).
```

Illustrate the differences between _self_ and _this_:

```logtalk
aircraft::context.
```

<!--
Running context/0 predicate definition in object "aircraft":
  self: aircraft
  this: aircraft
  sender: user

Running context/0 predicate definition in object "transport":
  self: aircraft
  this: transport
  sender: user

Running context/0 predicate definition in object "thing":
  self: aircraft
  this: thing
  sender: user

true.
-->
