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wrappers

This example illustrates how to use the begin_of_file term generated when compiling a source file to create an object wrapper for the code in a plain Prolog file. Assuming that the context_switching_calls is set to allow, the generated object predicates can be called using the (<<)/2 debugging control construct for testing. This wrapper is useful for e.g. using the Logtalk compiler lint checks to examine predicate call dependencies of the wrapped code and also to look for possible portability issues when the portability flag is set to warning.

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

%versions

Start by loading the hook object:

logtalk_load(wrappers(wrapper)).

Compile the zipper.pl plain Prolog source file using the hook object:

logtalk_load('zipper.pl', [hook(wrapper)]).

Try one of the generated zipper object predicates:

zipper<<(zipper(3, [1,2,3,4,5], Zip, X), next(Zip, Next)).