Null

A null-typed variable always holds the JavaScript value null. There's nothing to type: instead of a free-text default-value field, the Variables panel shows this as a locked value, since null is the only value this type can ever hold.

Compiles to

let placeholder = null;

Get Variable / Set Variable

A Get placeholder node reads it back; a Set placeholder node assigns a new value and continues:

Get Variable

Set Variable

Use case

• Intentionally empty placeholder: declare a variable as explicitly empty from the start, distinguishing "not yet set" from a real value, before something else assigns it later via a Set Variable node.

Related

• Get Variable / Set Variable — the generic node reference (ports, wiring rules).
• Variables overview — declaring a variable, keywords, and cross-canvas concepts (Export, Module Variables).