Source Code Markup
Synopsis
Documentation tags attach an inline concept description to any Rascal declaration. Inside the tag you can use an entire structure of a tutor concept.
Previously there was a single @doc
tag with all the sections
of a concept internally. Now we use different tags for each concept.
The old notation is deprecated but still supported for backward compatibility.
These tags will be used by the tutor compiler to document any Rascal declaration:
@synopsis
@description
@examples
@benefits
@pitfalls
The @synopsis
tag is not optional. The others are optional.
Description
All Rascal declarations can be preceeded by annotation of the form @synopsis{ ... }
where ... may be arbitrary text,
provided that {
and }
characters are balanced and that unbalanced braces are escaped like \{
or \}
.
This text is expanded to a full concept definition when the concept is processed.
The Tutor supports and expands inline concept descriptions for the following declarations types.
Module Declaration
The name of this module is extracted. The header of the concept definition is automatically generated and consists of:
---
title: _Module name_
---
<div class="theme-doc-version-badge badge badge--secondary">rascal-0.40.13-BOOT2</div> <div class="theme-doc-version-badge badge badge--secondary">rascal-tutor-0.19.9</div>
#### Usage
_Import declaration needed to use this module_
Function Declaration
The signatures of this function and of all directly following functions with the same name are collected. The signatures are placed in an itemized list (unless there is only one). The header of the concept definition is automatically generated and consists of:
---
title: _Function name_
---
<div class="theme-doc-version-badge badge badge--secondary">rascal-0.40.13-BOOT2</div> <div class="theme-doc-version-badge badge badge--secondary">rascal-tutor-0.19.9</div>
#### Function
```rascal
_Function signature_
```
####
Usage
_Import declaration needed to use this module_
Data Declaration
The signatures of this data declaration and of all directly following data declarations without their own @doc
annotation are collected.
The header of the concept definition is automatically generated and consists of:
#### Type
```rascal
_Data declarations_
```
#### Usage
_Import declaration needed to use this module_
Annotation Declaration
The signature of this annotation declaration is collected. The header of the concept definition is automatically generated and consists of:
#### Type
```rascal
_Annotation declarations_
```
#### Usage
_Import declaration needed to use this module_
Examples
We only give an example of documenting a simple function. Read the source code of Rascal library files for other ones.
Consider the source code of the now function in the DateTime
library.
@synopsis{Get the current datetime.}
@examples{
```rascal-shell
import DateTime;
now();
```
}
@javaClass{org.rascalmpl.library.DateTime}
public java datetime now();
This will be expanded to
#### Function
```rascal
datetime now();
```
#### Usage
```rascal
import DateTime;
```
#### Synopsis
Get the current datetime.
#### Examples
```rascal-shell
rascal> import DateTime;
ok
rascal> now();
datetime: $2024-11-06T13:09:14.904+00:00$
```
Benefits
- A (small) part of documentation writing is automated.
- The information about the name of a function, data or annotation declaration, or its signature is always consistent.
- Examples of how to use functions are maintained close to the definitions of those functions
- API documentation for Rascal modules is easily presented online or in an IDE.
Pitfalls
- This approach requires that functions with the same name are grouped together in the source file.
- Editor support for markdown inside @doc tags is usually limited.