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errors

This folder contains examples of objects, categories, and protocols containing errors and code issues that will trigger Logtalk compiler warnings and errors. The goal of this example is to help the user to get acquainted to the Logtalk compiler warning and error reporting. Open the source files in a text editor to better understand how the compiler deals with common programming errors.

Note that the warnings and errors that you will get while compiling your source files depend on your compiler flags (defined explicitly as parameters for the logtalk_compile/2 or logtalk_load/2 built-in predicates or by default in your Prolog adapter file and possibly overridden in your settings file). See the Handbook section on writing and running applications for a detailed description of the flags.

The tutor tool provides explanations and fix suggestions for compiler warnings and errors messages. New users are advised to load it at startup (e.g., from a settings file) for a more friendly experience.

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

%versions

To augment compiler warnings and errors messages with explanations and fix suggestions, start by loading the tutor tool:

logtalk_load(tutor(loader)).

The entities on this example are divided in two sets. The first set results on compiler warning messages, while the second set results in compiler error messages. To load each sets of entities, compile and load the corresponding loader files.

Illustrate common compiler errors:

logtalk_load(errors(warnings_loader)).

Illustrate common compiler warnings:

logtalk_load(errors(errors_loader)).