Add a %%cython cell magic

Author: vbraun

src/sage/misc/cython_c.pyx

@@ -2,6 +2,8 @@
 
 from sage.misc.temporary_file import tmp_filename
 from sage.misc.cython import cython_import_all
+from sage.repl.user_globals import get_globals
+
 
 def cython_compile(code,
           verbose=False, compile_message=False,
@@ -60,7 +62,7 @@ def cython_compile(code,
     """
     tmpfile = tmp_filename(ext=".spyx")
     open(tmpfile,'w').write(code)
-    cython_import_all(tmpfile, globals(),
+    cython_import_all(tmpfile, get_globals(),
                       verbose=verbose, compile_message=compile_message,
                       use_cache=use_cache,
                       create_local_c_file=False)

src/sage/repl/ipython_extension.py

@@ -15,6 +15,8 @@
 
   - ``%mode`` (like ``%maxima``, etc.)
 
+  - ``%%cython``
+
 * preparsing of input
 
 * loading Sage library
@@ -56,7 +58,7 @@
     sage: shell.quit()
 """
 
-from IPython.core.magic import Magics, magics_class, line_magic
+from IPython.core.magic import Magics, magics_class, line_magic, cell_magic
 
 from sage.repl.load import load_wrap
 from sage.env import SAGE_IMPORTALL, SAGE_STARTUP_FILE
@@ -321,6 +323,38 @@ def display(self, args):
             except ValueError as err:
                 print(err)  # do not show traceback
 
+    @cell_magic
+    def cython(self, line, cell):
+        """
+        Cython cell magic
+
+        This is syntactic sugar on the
+        :func:`~sage.misc.cython_c.cython` function.
+
+        INPUT::
+
+        - ``line`` -- ignored.
+
+        - ``cell`` -- string. The Cython source code to process.
+
+        OUTPUT:
+
+        None. The Cython code is compiled and loaded.
+
+        EXAMPLES::
+
+            sage: from sage.repl.interpreter import get_test_shell
+            sage: shell = get_test_shell()
+            sage: shell.run_cell('''
+            ....: %%cython
+            ....: def f():
+            ....:     print('test')
+            ....: ''')
+            ....: shell.run_cell('f()')
+        """
+        from sage.misc.cython_c import cython_compile
+        return cython_compile(cell)
+
 
 class SageCustomizations(object):