XXX Explain terminology, or come up with something more ``lay.''
There are a number of environments used to describe specific
features provided by modules. Each environment requires
parameters needed to provide basic information about what is being
described, and the environment content should be the description.
Most of these environments make entries in the general index (if
one is being produced for the document); if no index entry is
desired, non-indexing variants are available for many of these
environments. The environments have names of the form
featuredesc, and the non-indexing variants are named
featuredescni. The available variants are explicitly
included in the list below.
For each of these environments, the first parameter, name,
provides the name by which the feature is accessed.
Environments which describe features of objects within a module,
such as object methods or data attributes, allow an optional
type name parameter. When the feature is an attribute of
class instances, type name only needs to be given if the
class was not the most recently described class in the module; the
name value from the most recent \classdesc is implied.
For features of built-in or extension types, the type name
value should always be provided. Another special case includes
methods and members of general ``protocols,'' such as the
formatter and writer protocols described for the
formatter module: these may be documented without any
specific implementation classes, and will always require the
type name parameter to be provided.
Environment used to described a C function. The type
should be specified as a typedef name, struct
tag, or the name of a primitive type. If it is a pointer
type, the trailing asterisk should not be preceded by a space.
name should be the name of the function (or function-like
pre-processor macro), and args should give the types and
names of the parameters. The names need to be given so they may
be used in the description.
Description for a structure member. container should be
the typedef name, if there is one, otherwise if should
be "struct tag". The type of the member should given
as type, and the name should be given as name. The
text of the description should include the range of values
allowed, how the value should be interpreted, and whether the
value can be changed. References to structure members in text
should use the \member macro.
Documentation for a ``simple'' macro. Simple macros are macros
which are used for code expansion, but which do not take
arguments so cannot be described as functions. This is not to
be used for simple constant definitions. Examples of its use
in the Python documentation include
PyObject_HEAD and
Py_BEGIN_ALLOW_THREADS.
\begin{ctypedesc}[tag]{name} \end{ctypedesc}
Environment used to described a C type. The name
parameter should be the typedef name. If the type is
defined as a struct without a typedef,
name should have the form struct tag.
name will be added to the index unless tag is
provided, in which case tag will be used instead.
tag should not be used for a typedef name.
\begin{cvardesc}{type}{name} \end{cvardesc}
Description of a global C variable. type should be the
typedef name, struct tag, or the name of
a primitive type. If variable has a pointer type, the trailing
asterisk should not be preceded by a space.
\begin{datadesc}{name} \end{datadesc}
This environment is used to document global data in a module,
including both variables and values used as ``defined
constants.'' Class and object attributes are not documented
using this environment.
\begin{datadescni}{name} \end{datadescni}
Like \datadesc, but without creating any index entries.
Describe an exception defined by a class. constructor
parameters should not include the self parameter or
the parentheses used in the call syntax. To describe an
exception class without describing the parameters to its
constructor, use the \excdesc environment.
\begin{excdesc}{name} \end{excdesc}
Describe an exception. In the case of class exceptions, the
constructor parameters are not described; use \excclassdesc
to describe an exception class and its constructor.
\begin{funcdesc}{name}{parameters} \end{funcdesc}
Describe a module-level function. parameters should
not include the parentheses used in the call syntax. Object
methods are not documented using this environment. Bound object
methods placed in the module namespace as part of the public
interface of the module are documented using this, as they are
equivalent to normal functions for most purposes.
The description should include information about the parameters
required and how they are used (especially whether mutable
objects passed as parameters are modified), side effects, and
possible exceptions. A small example may be provided.
Describe a class and its constructor. constructor
parameters should not include the self parameter or
the parentheses used in the call syntax.
\begin{classdesc*}{name} \end{classdesc*}
Describe a class without describing the constructor. This can
be used to describe classes that are merely containers for
attributes or which should never be instantiated or subclassed
by user code.
Describe an object data attribute. The description should
include information about the type of the data to be expected
and whether it may be changed directly.
Describe an object method. parameters should not include
the self parameter or the parentheses used in the call
syntax. The description should include similar information to
that described for \funcdesc.
