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missing_data

This example illustrates how to use the expected terms library to decouple data acquisition, which must be able to succeed when unexpected events happen, from data processing, which decides how to handle those events.

For more details about this example, please see the comments in the expecteds.lgt source file.

See also the cascade and books examples.

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

%versions

Start by loading the example:

logtalk_load(missing_data(loader)).

In the first data processing example, we provide defaults for the missing data:

data_processing::print.

<!-- gomez father: john doe mother: jane doe

pubert father: gomez mother: morticia

pugsley father: gomez mother: morticia

morticia father: john doe mother: jane doe

wednesday father: gomez mother: morticia

true. -->

In the second data processing example, we simply skip missing data:

data_processing::print_complete.

<!-- pubert father: gomez mother: morticia

pugsley father: gomez mother: morticia

wednesday father: gomez mother: morticia

true. -->

In the third data processing example, we throw an error on missing data:

catch(data_processing::check, Error, true).