plastikfan / zenobia

Regular expression based file management library
MIT License
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Evaluate Expression Yield/Placeholder #9

Open plastikfan opened 5 years ago

plastikfan commented 5 years ago

The expression-builder needs to handle Yield/Placeholder elements.

The Yield element defines how to generate a string that conforms to the regular expression within which it is defined and can contain @open and @close attributes. These indicate how to process the placeholders.

The Placeholder references the fields delimited by @open and @close. The expression builder should be self contained, so we can't validate the fields at this point (there will later be an arbitraitor, that can resolve the "field-builder" and the "expression-builder", since they both rely on each other. Fields are linked to regular expressions, and regular expression contain Yields which can refer to fields.

The Placholder element can contain the following attributes: @ordinal = mandatory|optional: do this fields referenced exist r not? @contains-content (file system instruction): Does the folder currently being processed contain media type specified @is-present(csv of multiple fields): does the field referenced exist or not for the current folder being processed (More attributes may need to be defined)