Repository: cython/cython

Issue:
Document new features in Cython 3.0
It's time to look through the documentation to see if all new features have been documented and/or are findable for users in an appropriate place. This is a great beginners ticket because it allows playing with new Cython features and figuring out how they work.

- look through [CHANGES.rst](https://github.com/cython/cython/blob/master/CHANGES.rst) to see what features are new in the latest 3.0 alpha versions and which seem to be worth mentioning
- look in the documentation where you would expect this to be documented
- if it's already covered, perfect
- otherwise, search the documentation to see if it's mentioned elsewhere, and decide if that's the right place
- if not, write a paragraph or two and/or add a cross-ref from places where you think it's also worth mentioning
- if you add example code (examples are great!) make sure it compiles by adding it as a `.pyx` file under `docs/examples/` to let the test suite pick it up
- preferably, use separate commits/updates for the different features.


Discussion:
From a quick look through, features that stand out to me as currently undocumented include:

* cython-3.0.pxd versioning - probably should be documented. I'll submit a PR with a sentence or two for this.
* `cdef` properties. I wonder if the limitation to external cdef classes will be hard to explain without causing confusion?
* limited api - probably shouldn't be documented until its a little more complete.
* pythran - not strictly new to Cython 3, but I can find references to it in the changelog but no documentation at all. @serge-sans-paille ?
@da-woods : the official doc is scarce, but here it is: https://cython.readthedocs.io/en/latest/src/userguide/numpy_pythran.html 
By "`cdef` properties" do you mean the inlined `@property` decorator on `ctypedef class`es? That is documented as [C inline properties](https://cython.readthedocs.io/en/latest/src/userguide/extension_types.html#c-inline-properties).

So unless more refinement is needed, I think the three new features described here are documented (assuming "limited API" is not yet ready for prime time).
> By "`cdef` properties" do you mean the inlined `@property` decorator on `ctypedef class`es? That is documented as [C inline properties](https://cython.readthedocs.io/en/latest/src/userguide/extension_types.html#c-inline-properties).
> 
> So unless more refinement is needed, I think the three new features described here are documented (assuming "limited API" is not yet ready for prime time).

Yeah - the inlined `@property` decorator is what I meant. I don't think think more refinement is needed, so two out of the three features are documented (and limited API isn't ready yet)

Resolving patch:
diff --git a/Cython/Build/Dependencies.py b/Cython/Build/Dependencies.py
--- a/Cython/Build/Dependencies.py
+++ b/Cython/Build/Dependencies.py
@@ -948,6 +948,11 @@ def cythonize(module_list, exclude=None, nthreads=0, aliases=None, quiet=False,
                      See examples in :ref:`determining_where_to_add_types` or
                      :ref:`primes`.
 
+
+    :param annotate-fullc: If ``True`` will produce a colorized HTML version of
+                           the source which includes entire generated C/C++-code.
+
+
     :param compiler_directives: Allow to set compiler directives in the ``setup.py`` like this:
                                 ``compiler_directives={'embedsignature': True}``.
                                 See :ref:`compiler-directives`.
diff --git a/docs/conf.py b/docs/conf.py
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -44,7 +44,8 @@
     'sphinx.ext.imgmath',
     'sphinx.ext.todo',
     'sphinx.ext.intersphinx',
-    'sphinx.ext.autodoc'
+    'sphinx.ext.autodoc',
+    'sphinx_issues',  # if this is missing, pip install sphinx-issues
     ]
 
 try: import rst2pdf
@@ -135,6 +136,9 @@
 # The output image format. The default is 'png'. It should be either 'png' or 'svg'.
 imgmath_image_format = "svg"
 
+# For sphinx-issues
+
+issues_github_path = "cython/cython"
 
 # -- Options for HTML output ---------------------------------------------------
 


Test patch: