Error

relationalai.semantics.frontend.core

Error = include_in_docs(CoreEntities.Type('Error'))

A core Concept for emitting errors.

Use Error.new(...) inside Model.define to record an error when a condition matches. Each call creates an Error entity with a message and any extra keyword fields you provide, for example type="InvalidValue" which you can later read as Error.type.

If you define multiple errors, select the ones you want by filtering on Error.message and/or your context fields (for example Error.type == "InvalidValue").

You can inspect errors explicitly by selecting them, and they also surface as warnings when you run queries.

Examples

Define an error with context:

>>> from relationalai.semantics import Error, Integer, Model, String
>>> m = Model()
>>> Person = m.Concept("Person")
>>> Person.name = m.Property(f"{Person} has {String:name}")
>>> Person.age = m.Property(f"{Person} has {Integer:age}")
>>> m.define(Person.new(name="Alice", age=10))
>>> m.where(Person.age < 18).define(
...     Error.new(message="Person is too young", person=Person, age=Person.age)
... )

Select only matching errors:

>>> m.where(Error, Error.message == "Person is too young").select(
...     Error.message, Error.person.name, Error.age
... ).to_df()