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Design pattern:
	Facade

Description:
	"Provide a unified interface to a set of interfaces in a subsystem.
	Facade defines a higher-level interface that makes the subsystem
	easier to use."

This pattern can be used with both classes and prototypes. As a facade
object delegates the simplified client requests to the objects that
represent the abstracted subsystems, these subsystems can be implemented
using prototypes, classes, or a mix of both.

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

```logtalk
%versions
```

Start by loading the design pattern sample implementation:

```logtalk
logtalk_load(design_patterns('structural/facade/loader')).
```

Use the simplified interface provided by the facade to start the computer:

```logtalk
computer_facade(cpu, memory, ssd)::start.
```

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Or, in alternative:

```logtalk
computer_facade::start.
```

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