---
id: BR-2
family: RT-BR
level: core
profiles: [runtime]
posture: normative-target
added: "1.0"
changed: "1.0"
source: https://flowdrop.io/spec/rules/rt-br/br-2
specification: FlowDrop Workflow Specification 1.0-draft
licence: CC BY 4.0
---

# BR-2 — The three cases in which a branch decision never gates an edge

*RT-BR (Part II) · level: core · profiles: runtime · added in 1.0*

Read on its own, "follow the edge if its port is active" would strand every edge that has nothing to do with branching. These three cases are checked first and answer before the active-branch list is ever consulted.

## The rule

> **Normative.** This is the rule.
>
> 1. Three cases return "follow the edge" before membership of the active-branch list is tested, checked in this order: the source port is unnamed; the source emitted no active-branch list, or an empty one; and the port is a value port rather than a branch port.
>
> 2. A port is a branch port when the source declares it among its configured branches, matched without regard to case; a port the source does not so declare is a value port and is never gated.
>
> 3. A source that declares no branches at all therefore gates nothing, whatever it emitted: with no port declared a branch port, every edge leaving it is followed.

## Related rules

- Names: BR-1, BR-4
- Referenced by: BR-1, BR-4

---

Rule identifiers are permanent and are never renumbered. This specification carries
no implementation status: each implementation publishes its own standing against
these rules. Licensed CC BY 4.0.