Region
A region is one orthogonal part of a composite state, drawn as a tile with dashed separators. Regions lie across the flow: side by side when flowing down, stacked when flowing right.
diagram state "Regions"
state Active {
region "input" {
[*] --> Reading
Reading --> [*]
}
region "output" {
[*] --> Writing
Writing --> [*]
}
}
Syntax
region ["name"] { ... } inside a state
A transition cannot join two regions of one state.
Specification
UML 2.5.1, 14.2.4.3 (p. 319).