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A comment on Sequence diagrams, the only good thing UML brought to software development. Parent comment

Re:Sequence diagrams, the only good thing UML brought to sof... by knsv on Thursday June 15, 2023 @01:44PM (#36344074)
The problem with state machines that I run into often when using them, is "multi-dimensional" states.

When managing to get that right they are great, otherwise you get loads of edges...

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Re:Sequence diagrams, the only good thing UML brought to sof... by sidpatil on Thursday June 15, 2023 @01:49PM (#36344152)
I'm not sure what you mean by "multi-dimensional" states. Is it something that statecharts [1] can help with?

[1] https://statecharts.dev/

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Re:Sequence diagrams, the only good thing UML brought to sof... by barrkel on Thursday June 15, 2023 @03:23PM (#36345259)
The cross product of multiple state machines, I expect. If you try and use a single state diagram to encode the product of states, everything multiplies.
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Re:Sequence diagrams, the only good thing UML brought to sof... by michaelsbradley on Thursday June 15, 2023 @04:34PM (#36346141)
That’s where statecharts can help.
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Re:Sequence diagrams, the only good thing UML brought to sof... by RossBencina on Thursday June 15, 2023 @10:49PM (#36350457)
UML Statecharts are Harel Statecharts, which are hierarchical state machines. Described here:

Statecharts - A visual formalism for complex systems. David Harel. 1987

https://archive.org/details/7.-statecharts

Looks like you can also freely download the paper from here: https://www.sciencedirect.com/science/article/pii/0167642387...

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Re:Sequence diagrams, the only good thing UML brought to sof... by tonnydourado on Thursday June 15, 2023 @01:53PM (#36344196)
Not sure what you mean by multidimensional states?
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Re:Sequence diagrams, the only good thing UML brought to sof... by hwayne on Thursday June 15, 2023 @03:45PM (#36345499)
The car can be in drive, neutral, or reverse, the light can be red, green, yellow, or broken, the seatbelt can be off or on. That's 24 states.
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Re:Sequence diagrams, the only good thing UML brought to sof... by tonnydourado on Thursday June 15, 2023 @04:54PM (#36346395)
Ah, ok. That's kind of what I meant by upfront design, though. Yeah, mapping this out is gonna suck, but it's better than having it hidden in a bunch of ifs.
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