https://oprypin.github.io/mkdocs-code-validator/ https://github.com/crystal-lang/crystal-book/pull/503
1. run the code with some kind of plugin as part of your doc pipeline
2. generate documentation from your code
3. take some kind of hybrid approach
I went for 3., annotate snippet "areas" in the source code of a project (mainly in tests) and extract the snippets to a folder, e.g. into the mkdocs folder. I commit them to the (docs) repo. If the project changes, usually I fix the tests and update the snippets in mkdocs. This way I can be sure that the code in the documentation is actually working and people can copy&paste it. To scratch my own itch, I (surprise, surprise) created a script and even packaged it[1].
live snippets (brett victor hello) or even ability to try permutations of inputs to get a feel
and maybe .. metalevel generated live tests.
I attempted a Kotlin centric documentation framework a while ago to address this: https://github.com/jillesvangurp/kotlin4example
I mainly use it to generate the documentation for my Elasticsearch Kotlin Client (jillesvangurp/es-kotlin-client). The idea there is that all examples and source samples are correctly compiling Kotlin code that I can get the output of when they run (e.g. a println). Running the tests, actually generates the documentation markdown. Using a dsl and multiline strings, I can mix lambda code blocks, markdown, or markdown inside files. For the lambda blocks, it figures out the source and line numbers using reflection. But it can also grab source samples based on comment markers. For bigger blobs of markdown, it's easier to grab the content from markdown files. For smaller sections of markdown, I can use inline multi line strings or a Kotlin DSL.
The main benefit of this is that my examples update as I change and refactor the code base. Also, since it runs as part of my tests, I know when examples break.