A loopback driven from the trigger port belongs to no branch
The rule
Where a loopback edge's source is the reserved trigger port, the re-entry it drives is attributed to no branch.
What it means
A loopback edge's branch is read off the port it leaves its source by, and
trigger is a control signal, not a named branch — leaving by it extracts to
no branch at all. Where a source declares branches and gates re-entry by
which one fired, a loopback edge driven from trigger sits outside that
gate: the re-entry it drives happens regardless of which branch, if any, the
source reports as active.
Example
A loopback edge leaves its source by the reserved trigger port rather than by
a branch port such as the one whose handle ends in False.
"gw.1-output-trigger"""An empty branch name is what attributes a loopback edge to no branch; the
same extraction on a handle ending in False yields False.