5. Differences to the LaTeX markup

Python v2.7.1

5. Differences to the LaTeX markup

Though the markup language is different, most of the concepts and markup types of the old LaTeX docs have been kept – environments as reST directives, inline commands as reST roles and so forth.

However, there are some differences in the way these work, partly due to the differences in the markup languages, partly due to improvements in Sphinx. This section lists these differences, in order to give those familiar with the old format a quick overview of what they might run into.

5.1. Inline markup

These changes have been made to inline markup:

  • Cross-reference roles

    Most of the following semantic roles existed previously as inline commands, but didn’t do anything except formatting the content as code. Now, they cross-reference to known targets (some names have also been shortened):

    mod (previously refmodule or module)
    func (previously function)
    data (new)
    const
    class
    meth (previously method)
    attr (previously member)
    exc (previously exception)
    cdata
    cfunc (previously cfunction)
    cmacro (previously csimplemacro)
    ctype

    Also different is the handling of func and meth: while previously parentheses were added to the callable name (like \func{str()}), they are now appended by the build system – appending them in the source will result in double parentheses. This also means that :func:`str(object)` will not work as expected – use ``str(object)`` instead!

  • Inline commands implemented as directives

    These were inline commands in LaTeX, but are now directives in reST:

    deprecated
    versionadded
    versionchanged

    These are used like so:

    .. deprecated:: 2.5
       Reason of deprecation.
    

    Also, no period is appended to the text for versionadded and versionchanged.

    note
    warning

    These are used like so:

    .. note::
    
       Content of note.
    
  • Otherwise changed commands

    The samp command previously formatted code and added quotation marks around it. The samp role, however, features a new highlighting system just like file does:

    :samp:`open({filename}, {mode})` results in open(filename, mode)

  • Dropped commands

    These were commands in LaTeX, but are not available as roles:

    bfcode
    character (use ``'c'``)
    citetitle (use `Title <URL>`_)
    code (use ``code``)
    email (just write the address in body text)
    filenq
    filevar (use the {...} highlighting feature of file)
    programopt, longprogramopt (use option)
    ulink (use `Title <URL>`_)
    url (just write the URL in body text)
    var (use *var*)
    infinity, plusminus (use the Unicode character)
    shortversion, version (use the |version| and |release| substitutions)
    emph, strong (use the reST markup)
  • Backslash escaping

    In reST, a backslash must be escaped in normal text, and in the content of roles. However, in code literals and literal blocks, it must not be escaped. Example: :file:`C:\\Temp\\my.tmp` vs. ``open("C:\Temp\my.tmp")``.

5.2. Information units

Information units (...desc environments) have been made reST directives. These changes to information units should be noted:

  • New names

    “desc” has been removed from every name. Additionally, these directives have new names:

    cfunction (previously cfuncdesc)
    cmacro (previously csimplemacrodesc)
    exception (previously excdesc)
    function (previously funcdesc)
    attribute (previously memberdesc)

    The classdesc* and excclassdesc environments have been dropped, the class and exception directives support classes documented with and without constructor arguments.

  • Multiple objects

    The equivalent of the ...line commands is:

    .. function:: do_foo(bar)
                  do_bar(baz)
    
       Description of the functions.
    

    IOW, just give one signatures per line, at the same indentation level.

  • Arguments

    There is no optional command. Just give function signatures like they should appear in the output:

    .. function:: open(filename[, mode[, buffering]])
    
       Description.
    

    Note: markup in the signature is not supported.

  • Indexing

    The ...descni environments have been dropped. To mark an information unit as unsuitable for index entry generation, use the noindex option like so:

    .. function:: foo_*
       :noindex:
    
       Description.
    
  • New information units

    There are new generic information units: One is called “describe” and can be used to document things that are not covered by the other units:

    .. describe:: a == b
    
       The equals operator.
    

    The others are:

    .. cmdoption:: -O
    
       Describes a command-line option.
    
    .. envvar:: PYTHONINSPECT
    
       Describes an environment variable.
    

5.3. Structure

The LaTeX docs were split in several toplevel manuals. Now, all files are part of the same documentation tree, as indicated by the toctree directives in the sources (though individual output formats may choose to split them up into parts again). Every toctree directive embeds other files as subdocuments of the current file (this structure is not necessarily mirrored in the filesystem layout). The toplevel file is contents.rst.

However, most of the old directory structure has been kept, with the directories renamed as follows:

  • api -> c-api
  • dist -> distutils, with the single TeX file split up
  • doc -> documenting
  • ext -> extending
  • inst -> installing
  • lib -> library
  • mac -> merged into library, with mac/using.tex moved to using/mac.rst
  • ref -> reference
  • tut -> tutorial, with the single TeX file split up