https://github.com/eglimi/cppfsm

A simple, generic, header-only state machine implementation for C++.
https://github.com/eglimi/cppfsm

c-plus-plus state-machine

Last synced: 3 months ago
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A simple, generic, header-only state machine implementation for C++.

• Host: GitHub
• URL: https://github.com/eglimi/cppfsm
• Owner: eglimi
• License: mit
• Created: 2014-12-18T09:33:47.000Z (almost 10 years ago)
• Default Branch: main
• Last Pushed: 2022-01-29T18:25:30.000Z (almost 3 years ago)
• Last Synced: 2024-05-02T20:13:53.233Z (6 months ago)
• Topics: c-plus-plus, state-machine
• Language: C++
• Size: 261 KB
• Stars: 58
• Watchers: 5
• Forks: 16
• Open Issues: 1
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

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README

        
Finite State Machine for C++

============================

A simple, generic, header-only state machine implementation for C++.

Documentation

-------------

Please see the documentation in [fsm.h](./fsm.h) for detailed documentation

about the implemented features and semantics.

Some more information about this component can also be found on our website. See [article 1] for the motivation, and [article 2] for the implementation.

[article 1]: http://wisol.ch/w/articles/2015-01-04-state-machine-intro/

[article 2]: http://wisol.ch/w/articles/2015-03-27-state-machine-impl/

Usage

-----

The implementation is contained in a single header file, `fsm.h`. Simply copy

the file to a convenient place in your project and include it.

Example

-------

As an example, consider the state machine below. It starts in state `A`. When

it receives the `exec` trigger, it checks that the `count` variable is `1`,

increments it, and changes to state `B`.

~~~

       +------+  Exec[count=1] / count++    +------+

  o--->|  A   |---------------------------->|  B   |

       +------+                             +------+

~~~

The implementation of this state machine is done in a declarative way.

~~~

int count = 1;

enum class States { A, B };

enum class Triggers { Exec };

FSM::Fsm fsm;

fsm.add_transitions({

//  from state ,to state  ,triggers        ,guard                    ,action

  { States::A  ,States::B ,Triggers::Exec  ,[&]{return count == 1;}  ,[&]{count++;} },

});

fsm.execute(Triggers::Exec);

assert(count == 2);

assert(fsm.state() == States::B);

~~~

See the tests for more examples.

Stability

---------

The implementation is already in use in different commercial applications. We

have not found any issues so far. Please report any problems you find.

Tests

-----

Tests can be run with

~~~

cd tests

g++ -std=c++11 -Wall -o tests fsm_test.cpp

./tests

~~~

Contributions

-------------

Contributions are welcome. Please use the Github issue tracker.