wardle / hermes

A library and microservice implementing the health and care terminology SNOMED CT with support for cross-maps, inference, fast full-text search, autocompletion, compositional grammar and the expression constraint language.
Eclipse Public License 2.0
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ECL expansion in which attribute values resolve to nothing result in an error #61

Closed wardle closed 11 months ago

wardle commented 11 months ago

When a subexpression is used for an attribute value, if that subexpression doesn't not resolve to any values, then Hermes currently reports an error suggesting an invalid attribute clause. This is incorrect. The correct behaviour is that the subexpression should resolve to a clause that matches no documents.