Default

The Default operation substitutes a configured value whenever its input arrives empty. A value that is present passes through untouched; a Nil — or an input port that was never connected — is replaced by the Default value you configured. It is the one-Node answer to “this reading is sometimes missing, and downstream needs a number regardless”.

Inputs

Port	Type	Required	Description
In	Any	Yes	The value to pass through. Nil — or an unconnected port — yields the Default value instead.

Outputs

Port	Type	Default	Description
Out	follows Default value	Nil	In when it carries a value, otherwise the Default value.

Properties

Name	Type	Default	Description
Default value	StackedDataSet	String	The substitute, and the branch that types it (see below).
String	String	(empty)	Substitute a text value.
Integer	Integer	(empty)	Substitute a whole number.
Double	Number	(empty)	Substitute a floating-point number.
Boolean	Boolean	(empty)	Substitute true or false.
On Error	Combo	Stop this branch	Per-op On Error verb (Stop this branch / Continue with the last value / Continue with the fallback). See the Error Handling guide.

State on Reload

Default holds no state. Every run is decided by the value in front of it, so there is nothing to preserve and nothing to discard.

No gate, and no way to fail

Default has no Gate input and no On Error verb. It cannot fail: an absent input is not an error condition here, it is precisely the case the operation exists to answer. The path always continues.

The branch you pick types the output

Out takes its type from the selected Default value branch, not from In. Pick the branch that matches what downstream ports expect — choosing String and feeding the result into a numeric port makes the graph refuse to compile.

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How It Works

1. Read the input — Out is written with In when that carries any value at all, including 0, false and the empty string.

2. Substitute — when In is Nil, or the port was never connected, Out is written with the configured Default value.

3. Continue — the path always continues.

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Examples

Value present

Default value: Integer = 20   In: 23

Out: 23

Value missing

Default value: Integer = 20   In: Nil

Out: 20

Falsy values pass through

Default value: Boolean = true   In: false

Out: false  (false is a value, not an absence)

Empty string passes through

Default value: String = "unknown"   In: ""

Out: ""  (an empty string is a value; only Nil substitutes)

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Use Cases

• Filling a gap from a parser — a JsonParser output for a field the payload omitted is Nil; Default supplies the value the rest of the graph needs.
• A safe starting value — give a computed setpoint a sensible figure before the first real reading arrives.
• Keeping a Report readable — substitute a placeholder so a rendered line reads "unknown" rather than showing an empty slot.

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Limitations

• The substitute is fixed at configuration time; it cannot be driven from an input port. To choose between two live values, use Condition.
• Only Nil substitutes. If an upstream producer signals “missing” with a sentinel such as -1 or "", convert that to a decision with Compare and Condition instead.