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object_aliases

This is a minimal example illustrating the use of the uses/1 directive to experiment with different object implementations of the same protocol when using explicit message-sending. The main idea is to have a single source line that can be edited to switch between different implementations as all message-sending calls would be written using the object alias. This is an alternative to accomplish the same goal by using a uses/2 directive and implicit message-sending. Note that both alternatives allow compiling the code in optimized mode to take advantage of static binding for the message-sending calls.

This example also illustrates defining an alias for an object defined at runtime using a parameter variable.

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

%versions

Start by loading the example:

logtalk_load(object_aliases(loader)).

Demonstration of using aliases for shorten object names and simplify trying alternative implementations:

experiments::stats(TotalLess, TotalEqual, TotalGreater), Total is TotalLess + TotalEqual + TotalGreater.

Demonstration of using aliases for objects defined at runtime using parameters.

Using the heap(<) library object, insert all elements in a list and return the top element:

simple(<)::insert_top([3-c,1-a,2-b], Top).

Using the heap(>) library object, insert all elements in a list and return the top element:

simple(>)::insert_top([3-c,1-a,2-b], Top).