14.8 Library-recoverable hard failure

A library-recoverable hard failure is a type of partially recoverable hard failure. Loosely described, it is a hard failure that allows the programmer to continue to use many of the Libmarpa methods in the library, but that disallows certain methods on some objects.

To state the restrictions of application behaviors more precisely, let the “failure grammar” be the base grammar of the method that detected the library-recoverable hard failure. After a library-recoverable hard failure, the following behaviors are no longer application behaviors:

• Libmarpa mutator and constructor method calls where the base grammar is the failure grammar.

Recall that any use of a behavior that is not an application behavior is an irrecoverable failure.

The application behaviors remaining after a library-recoverable hard failure are the following:

• All non-Libmarpa interfaces, including calls to libraries in the application and in the application environment.
• All Libmarpa static method calls.
• All Libmarpa accessor and destructor method calls.
• All Libmarpa mutator and constructor method calls whose base grammar is not the failure grammar.

Note that Libmarpa destructors remain available after a library recoverable failure. An application will often want to destroy all Libmarpa objects whose base grammar is the failure grammar, in order to clear memory of problematic objects.

An example of a library-recoverable hard failure is the MARPA_ERR_COUNTED_NULLABLE error in the marpa_g_precompute method. See marpa_g_precompute().