libdo

libdo is an embeddable library for predicate-driven programming in C and C++.

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Features

• C89 compatible
• Simple API
• Priority based dispatch
• Expirable handlers
• No restrictions on adding/removing handlers from within handlers
• Test suites

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Installation

git clone https://github.com/Sufi-Al-Hussaini/libdo.git

Copy libdo.{h,c} and vector.h to your source code tree and add libdo.c to your build system source files list.

Run make to compile C & C++ tests and ./tests or ./testscpp to run them.

For Arduino

• Create a directory named libdo in your ~/Arduino/libraries directory.
• Copy libdo.{h,c} and vector.h into it.
• Import the libdo library as usual. Typically, Sketch -> Include Library -> libdo in the Arduino IDE.

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Usage

Note: Error-checking removed for brevity.

/* Create a doer */
struct do_doer *doer = do_init();

/* Create a work with a work function and predicate */
bool run_work = true;
struct do_work *work = do_work_if(work_function, NULL, &run_work);

/* Ask the doer to do it */
/* This also gives up ownership of the work instance to the doer */
do_so(doer, work);

/* Call the loop() method */
/* This calls all work functions whose associated predicate evaluates to true */
while (do_loop(doer)) {
    sleep(1);
}

/* Cleanup */
do_destroy(doer);

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Documentation

Documentation and possible applications can be found on this blog post.

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Best practices

• Don't sleep in your predicate or work functions. Instead, add a work with a time predicate, if you want to do something after a delay.
• Add a delay between subsequent loop() calls, to keep the processor happy. Ideally, have a blocking function call before the loop() call.
• Make sure you remove works that you don't need.

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Todo

Work for these features is planned and under way:

• Code documentation
• C++11 header-only wrapper class
• Examples

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Contributing

• Submit pull requests for bug-fixes directly.
• For everything else (feature request, feature addition, discussions, etc.) open an issue first, so that it is easy for everyone to track.
• Follow libdo's code style and write appropriate test.

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License

The MIT License (MIT)