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Version: v4.24

assert

Drops event and emits a warning if the invariant is violated.

assert invariant:bool

Description​

The assert operator asserts that invariant is true for events. In case an event does not satisfy the invariant, it is dropped and a warning is emitted. The only difference between assert and where is that latter does not emit such a warning.

Examples​

Make sure that all events satisfy x > 2​

from [{x: 1}, {x: 2}, {x: 1}]
assert x > 2
{x: 1}
// warning: assertion failure
{x: 1}

Check that a topic only contains certain events​

subscribe "network"
assert @name == "ocsf.network_activity"
// continue processing