Noteref helps you make notes in your codebase and maintain references to them. This is particularly useful for documenting preconditions, postconditions, invariants, and other kinds of assumptions that aren't enforced by your tooling. For example, you might have a note like this:
```ruby
def wibble(x) ... end ```
Elsewhere, suppose you're writing some code that depends on that postcondition. You can make this clear by referencing the note:
```ruby flobs = wibble(wobble)
return flobs[0] # This is safe due to [ref:wibble_nonempty]. ```
Noteref ensures such references stay up-to-date. For example, if someone changes the behavior of wibble and deletes the note, Noteref will complain because there is some code that references it.
Whoever wanted to change wibble will have to preserve the invariant or fix any code that was relying on it to make Noteref happy:
So what does Noteref do exactly? It recursively scans a directory and checks the following:
The syntax is [note:label] for notes and [ref:label] for references. Noteref works with any programming language, and it respects your .gitignore file as well as other common filter files. It is highly recommended to set up Noteref as an automated continuous integration check. Noteref is fast and probably won't be the bottleneck in your CI.
The easiest way to use Noteref is to run the noteref command with no arguments. It will scan the working directory and check the two conditions described above. Here are the supported command-line options:
``` USAGE: noteref [FLAGS] [OPTIONS]
FLAGS: -h, --help Prints help information -n, --list-notes List all the notes. -r, --list-refs List all the refs. -V, --version Prints version information
OPTIONS:
-p, --path
The idea for Noteref was inspired by the GHC notes convention. GHC is one of the most maintainable codebases for its size. This article has more insights into how the GHC developers manage that codebase.