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logs

This folder contains an example of using a category to define a simple logging support for objects. This example illustrates how to define in a category a set of predicates that handle a dynamic predicate in the context of this.

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

%versions

Start by loading the example:

logtalk_load(logs(loader)).

The object log is automatically initialized when the object is loaded:

object::print_log.

<!-- 2008/7/17-18:15:38 - start

true. -->

Add a new entry to the object log:

object::add_log_entry('something interesting happens').

Check current object log:

object::print_log.

<!-- 2008/7/17-18:15:38 - start 2008/7/17-18:18:10 - something interesting happens

true. -->

In alternative, enumerate all log entries using backtracking:

%%table
object::log_entry(Date, Entry).