+ sequenceDiagram
+ Alice->>Bob: Hello Bob, how are you?
+ Bob-->>John: How about you John?
+ Bob--xAlice: I am good thanks!
+ Bob-xJohn: I am good thanks!
+ Note right of John: Bob thinks a long long time, so long that the text does not fit on a row.
+
+ Bob-->Alice: Checking with John...
+ Alice->John: Yes... John, how are you?
+
+
Loops, alt and opt
+
+ sequenceDiagram
+ loop Daily query
+ Alice->>Bob: Hello Bob, how are you?
+ alt is sick
+ Bob->>Alice: Not so good :(
+ else is well
+ Bob->>Alice: Feeling fresh like a daisy
+ end
+ opt Extra response
+ Bob->>Alice: Thanks for asking
+ end
+
+ end
+
+
Message to self in loop
+
+ sequenceDiagram
+ participant Alice
+ participant Bob
+ Alice->>John: Hello John, how are you?
+ loop Healthcheck
+ John->>John: Fight against hypochondria
+ end
+ Note right of John: Rational thoughts prevail...
+ John-->>Alice: Great!
+ John->>Bob: How about you?
+ Bob-->>John: Jolly good!
+
+
Bounding test & async message to self
+
+ sequenceDiagram
+ participant Alice
+ participant Bob
+ participant John the Long
+ Alice->Bob: Hello Bob, how are you?
+ loop Outer loop
+ Note left of Alice: Bob thinks about things to think about
+ Bob-xBob: I am good thanks!
+ loop Inner loop
+ Bob->>John the Long: How about you John?
+ Note right of John the Long: Bob thinks a long long time, so long that the text does not fit.
+ end
+ end
+
+ Bob-->>Alice: Checking with John...
+ Alice->>John the Long: Yes... John, how are you?
+ John the Long-->>Alice: Super!
+