Is null?
Description
Pure function returning true if the value is null. Generic on the value, in shape as well as type: a scalar, an array, a map or a whole model value can be connected, and the type is fixed at design-time when it is. Nulls reach a pipeline from optional model fields that parsed as JSON null.
When to use
Use Is null? to tell a missing value apart from a present-but-empty one. A model field
that is not required comes through as null when the payload omits it or sends
null — which is different from an empty string or a zero, and Is empty? cannot tell
you which you have. The same applies to whole collections and nested models: a payload
that sends "items": null is not the same as one that sends [], so an array, a map or
a model value can be wired straight into the Value pin. Wire the Result output into
Branch to take a different path when data is absent. If all you want is a stand-in
value, Default if null does it in one node without branching.
Pins
Input pins
| Pin | Type | Default | Notes |
|---|---|---|---|
| Value | generic | — | The value to test. The type resolves at design-time from the connected source, and so does the shape: an array, a map or a whole model value is as testable as a scalar. An unconnected pin has no value, so the result is true. |
Output pins
| Pin | Type | Notes |
|---|---|---|
| Result | boolean | True when the value is null. An empty string, a zero and a false are all present values, so they return false. |
Example
Take a different path when an optional field is missing. Parse an inbound payload with Parse to model, wire the Value output into Break, then wire the optional field’s output into the Value input of Is null?. Connect the Result output to the Condition input of Branch — the True execution output handles the missing-data case, the False output continues with the value.