Transcribe is a simple program which generates Markdown documentation from code comments.
The general idea is that each "export" should be accompanied by a "docstring".
The first line of the "docstring" should be a Haskell-inspired type signature
in the form <heading-prefix> <name> :: <type>.
//# map :: (a -> b) -> Array a -> Array b
//.
//. Transforms a list of elements of type `a` into a list of elements
//. of type `b` using the provided function of type `a -> b`.
//.
//. ```javascript
//. > map (String) ([1, 2, 3, 4, 5])
//. ['1', '2', '3', '4', '5']
//. ```
const map = f => xs => {
const output = [];
for (let idx = 0; idx < xs.length; idx += 1) {
output.push (f (xs[idx]));
}
return output;
};The --heading-prefix option specifies which lines in the source files
contain type signatures to become headings in the output. The default value
is //#; specify a different value if using a different comment style. For
example:
--heading-prefix '#%'
The --prefix option specifies which lines in the source files should
appear in the output along with the lines prefixed with <heading-prefix>.
The default value is //.; specify a different value if using a different
comment style. For example:
--prefix '#.'
Each line beginning with zero or more whitespace characters followed by the
prefix is included in the output, sans prefix and leading whitespace. The .
in the default prefix makes it possible to be selective about which comments
are included in the output: comments such as // Should never get here! will
be ignored.
The --url option specifies a template for generating links to specific
lines of source code on GitHub or another code-hosting site. The value should
include {filename} and {line} placeholders to be replaced with the filename
and line number of each of the signature lines. For example:
--url 'https://github.com/plaid/sanctuary/blob/v0.4.0/{filename}#L{line}'
Avoid pointing to a moving target: include a tag name or commit hash rather
than a branch name such as main.
The --heading-level option specifies the heading level, an integer in
range [1, 6]. The default value is 3, which corresponds to an <h3>
element in HTML. Specify a different value if desired. For example:
--heading-level 4
The --insert-into option specifies the name of a file into which
Transcribe will insert the generated output. By default, Transcribe writes to
stdout. However, if --insert-into is provided, Transcribe will insert the
output in the specified file between two special tags: <!--transcribe--> and
<!--/transcribe-->. For example:
--insert-into README.md
The options should be followed by one or more filenames. The filenames may
be separated from the options by --. Files are processed in the order in
which they are specified.
Here's a complete example:
$ transcribe \
> --url 'https://github.com/plaid/example/blob/v1.2.3/{filename}#L{line}' \
> -- examples/fp.js
### <a name="map" href="https://github.com/plaid/example/blob/v1.2.3/examples/fp.js#L3">`map :: (a -> b) -> Array a -> Array b`</a>
Transforms a list of elements of type `a` into a list of elements
of type `b` using the provided function of type `a -> b`.
```javascript
> map (String) ([1, 2, 3, 4, 5])
['1', '2', '3', '4', '5']
```
### <a name="filter" href="https://github.com/plaid/example/blob/v1.2.3/examples/fp.js#L21">`filter :: (a -> Boolean) -> Array a -> Array a`</a>
Returns the list of elements which satisfy the provided predicate.
```javascript
> filter (n => n % 2 === 0) ([1, 2, 3, 4, 5])
[2, 4]
```
By default, the output is written to stdout. One could redirect it to a file to generate lightweight API documentation:
$ printf '\n## API\n\n' >>README.md
$ transcribe \
> --url 'https://github.com/plaid/example/blob/v1.2.3/{filename}#L{line}' \
> -- examples/fp.js >>README.md
Reading from stdin is not currently supported.
One could also insert the output into an existing file by providing the
--insert-into option:
$ transcribe \
> --url 'https://github.com/plaid/example/blob/v1.2.3/{filename}#L{line}' \
> --insert-into README.md
> -- examples/fp.js