6 files changed, 186 insertions, 90 deletions
diff --git a/docs/examples/userguide/buffer/matrix.py b/docs/examples/userguide/buffer/matrix.py
new file mode 100644
index 000000000..0e431163d
--- /dev/null
+++ b/docs/examples/userguide/buffer/matrix.py
@@ -0,0 +1,15 @@
+# distutils: language = c++
+
+from cython.cimports.libcpp.vector import vector
+
+@cython.cclass
+class Matrix:
+    ncols: cython.uint
+    v: vector[cython.float]
+
+    def __cinit__(self, ncols: cython.uint):
+        self.ncols = ncols
+
+    def add_row(self):
+        """Adds a row, initially zero-filled."""
+        self.v.resize(self.v.size() + self.ncols)
diff --git a/docs/examples/userguide/buffer/matrix.pyx b/docs/examples/userguide/buffer/matrix.pyx
index abdb2d3c7..f2547f6c3 100644
--- a/docs/examples/userguide/buffer/matrix.pyx
+++ b/docs/examples/userguide/buffer/matrix.pyx
@@ -1,16 +1,15 @@
-# distutils: language = c++
-
-# matrix.pyx
-
-from libcpp.vector cimport vector
-
-cdef class Matrix:
-    cdef unsigned ncols
-    cdef vector[float] v
-
-    def __cinit__(self, unsigned ncols):
-        self.ncols = ncols
-
-    def add_row(self):
-        """Adds a row, initially zero-filled."""
-        self.v.resize(self.v.size() + self.ncols)
+# distutils: language = c++
+
+from libcpp.vector cimport vector
+
+
+cdef class Matrix:
+    cdef unsigned ncols
+    cdef vector[float] v
+
+    def __cinit__(self, unsigned ncols):
+        self.ncols = ncols
+
+    def add_row(self):
+        """Adds a row, initially zero-filled."""
+        self.v.resize(self.v.size() + self.ncols)
diff --git a/docs/examples/userguide/buffer/matrix_with_buffer.py b/docs/examples/userguide/buffer/matrix_with_buffer.py
new file mode 100644
index 000000000..34ccc6591
--- /dev/null
+++ b/docs/examples/userguide/buffer/matrix_with_buffer.py
@@ -0,0 +1,48 @@
+# distutils: language = c++
+from cython.cimports.cpython import Py_buffer
+from cython.cimports.libcpp.vector import vector
+
+@cython.cclass
+class Matrix:
+    ncols: cython.Py_ssize_t
+    shape: cython.Py_ssize_t[2]
+    strides: cython.Py_ssize_t[2]
+    v: vector[cython.float]
+
+    def __cinit__(self, ncols: cython.Py_ssize_t):
+        self.ncols = ncols
+
+    def add_row(self):
+        """Adds a row, initially zero-filled."""
+        self.v.resize(self.v.size() + self.ncols)
+
+    def __getbuffer__(self, buffer: cython.pointer(Py_buffer), flags: cython.int):
+        itemsize: cython.Py_ssize_t = cython.sizeof(self.v[0])
+
+        self.shape[0] = self.v.size() // self.ncols
+        self.shape[1] = self.ncols
+
+        # Stride 1 is the distance, in bytes, between two items in a row;
+        # this is the distance between two adjacent items in the vector.
+        # Stride 0 is the distance between the first elements of adjacent rows.
+        self.strides[1] = cython.cast(cython.Py_ssize_t, (
+             cython.cast(cython.p_char, cython.address(self.v[1]))
+           - cython.cast(cython.p_char, cython.address(self.v[0]))
+           )
+       )
+        self.strides[0] = self.ncols * self.strides[1]
+
+        buffer.buf = cython.cast(cython.p_char, cython.address(self.v[0]))
+        buffer.format = 'f'                     # float
+        buffer.internal = cython.NULL           # see References
+        buffer.itemsize = itemsize
+        buffer.len = self.v.size() * itemsize   # product(shape) * itemsize
+        buffer.ndim = 2
+        buffer.obj = self
+        buffer.readonly = 0
+        buffer.shape = self.shape
+        buffer.strides = self.strides
+        buffer.suboffsets = cython.NULL         # for pointer arrays only
+
+    def __releasebuffer__(self, buffer: cython.pointer(Py_buffer)):
+        pass
diff --git a/docs/examples/userguide/buffer/matrix_with_buffer.pyx b/docs/examples/userguide/buffer/matrix_with_buffer.pyx
index 985991cbe..fc2c160f3 100644
--- a/docs/examples/userguide/buffer/matrix_with_buffer.pyx
+++ b/docs/examples/userguide/buffer/matrix_with_buffer.pyx
@@ -1,45 +1,48 @@
-# distutils: language = c++
-
-from cpython cimport Py_buffer
-from libcpp.vector cimport vector
-
-cdef class Matrix:
-    cdef Py_ssize_t ncols
-    cdef Py_ssize_t shape[2]
-    cdef Py_ssize_t strides[2]
-    cdef vector[float] v
-
-    def __cinit__(self, Py_ssize_t ncols):
-        self.ncols = ncols
-
-    def add_row(self):
-        """Adds a row, initially zero-filled."""
-        self.v.resize(self.v.size() + self.ncols)
-
-    def __getbuffer__(self, Py_buffer *buffer, int flags):
-        cdef Py_ssize_t itemsize = sizeof(self.v[0])
-
-        self.shape[0] = self.v.size() / self.ncols
-        self.shape[1] = self.ncols
-
-        # Stride 1 is the distance, in bytes, between two items in a row;
-        # this is the distance between two adjacent items in the vector.
-        # Stride 0 is the distance between the first elements of adjacent rows.
-        self.strides[1] = <Py_ssize_t>(  <char *>&(self.v[1])
-                                       - <char *>&(self.v[0]))
-        self.strides[0] = self.ncols * self.strides[1]
-
-        buffer.buf = <char *>&(self.v[0])
-        buffer.format = 'f'                     # float
-        buffer.internal = NULL                  # see References
-        buffer.itemsize = itemsize
-        buffer.len = self.v.size() * itemsize   # product(shape) * itemsize
-        buffer.ndim = 2
-        buffer.obj = self
-        buffer.readonly = 0
-        buffer.shape = self.shape
-        buffer.strides = self.strides
-        buffer.suboffsets = NULL                # for pointer arrays only
-
-    def __releasebuffer__(self, Py_buffer *buffer):
-        pass
+# distutils: language = c++
+from cpython cimport Py_buffer
+from libcpp.vector cimport vector
+
+
+cdef class Matrix:
+    cdef Py_ssize_t ncols
+    cdef Py_ssize_t[2] shape
+    cdef Py_ssize_t[2] strides
+    cdef vector[float] v
+
+    def __cinit__(self, Py_ssize_t ncols):
+        self.ncols = ncols
+
+    def add_row(self):
+        """Adds a row, initially zero-filled."""
+        self.v.resize(self.v.size() + self.ncols)
+
+    def __getbuffer__(self, Py_buffer *buffer, int flags):
+        cdef Py_ssize_t itemsize = sizeof(self.v[0])
+
+        self.shape[0] = self.v.size() // self.ncols
+        self.shape[1] = self.ncols
+
+        # Stride 1 is the distance, in bytes, between two items in a row;
+        # this is the distance between two adjacent items in the vector.
+        # Stride 0 is the distance between the first elements of adjacent rows.
+        self.strides[1] = <Py_ssize_t>(  <char *>&(self.v[1])
+                                       - <char *>&(self.v[0]))
+
+
+
+        self.strides[0] = self.ncols * self.strides[1]
+
+        buffer.buf = <char *>&(self.v[0])
+        buffer.format = 'f'                     # float
+        buffer.internal = NULL                  # see References
+        buffer.itemsize = itemsize
+        buffer.len = self.v.size() * itemsize   # product(shape) * itemsize
+        buffer.ndim = 2
+        buffer.obj = self
+        buffer.readonly = 0
+        buffer.shape = self.shape
+        buffer.strides = self.strides
+        buffer.suboffsets = NULL                # for pointer arrays only
+
+    def __releasebuffer__(self, Py_buffer *buffer):
+        pass
diff --git a/docs/examples/userguide/buffer/view_count.py b/docs/examples/userguide/buffer/view_count.py
new file mode 100644
index 000000000..6a0554abc
--- /dev/null
+++ b/docs/examples/userguide/buffer/view_count.py
@@ -0,0 +1,30 @@
+# distutils: language = c++
+
+from cython.cimports.cpython import Py_buffer
+from cython.cimports.libcpp.vector import vector
+
+@cython.cclass
+class Matrix:
+
+    view_count: cython.int
+
+    ncols: cython.Py_ssize_t
+    v: vector[cython.float]
+    # ...
+
+    def __cinit__(self, ncols: cython.Py_ssize_t):
+        self.ncols = ncols
+        self.view_count = 0
+
+    def add_row(self):
+        if self.view_count > 0:
+            raise ValueError("can't add row while being viewed")
+        self.v.resize(self.v.size() + self.ncols)
+
+    def __getbuffer__(self, buffer: cython.pointer(Py_buffer), flags: cython.int):
+        # ... as before
+
+        self.view_count += 1
+
+    def __releasebuffer__(self, buffer: cython.pointer(Py_buffer)):
+        self.view_count -= 1
diff --git a/docs/examples/userguide/buffer/view_count.pyx b/docs/examples/userguide/buffer/view_count.pyx
index ee8d5085d..8c4b1d524 100644
--- a/docs/examples/userguide/buffer/view_count.pyx
+++ b/docs/examples/userguide/buffer/view_count.pyx
@@ -1,29 +1,30 @@
-# distutils: language = c++
-
-from cpython cimport Py_buffer
-from libcpp.vector cimport vector
-
-cdef class Matrix:
-
-    cdef int view_count
-
-    cdef Py_ssize_t ncols
-    cdef vector[float] v
-    # ...
-
-    def __cinit__(self, Py_ssize_t ncols):
-        self.ncols = ncols
-        self.view_count = 0
-
-    def add_row(self):
-        if self.view_count > 0:
-            raise ValueError("can't add row while being viewed")
-        self.v.resize(self.v.size() + self.ncols)
-
-    def __getbuffer__(self, Py_buffer *buffer, int flags):
-        # ... as before
-
-        self.view_count += 1
-
-    def __releasebuffer__(self, Py_buffer *buffer):
-        self.view_count -= 1
-\ No newline at end of file
+# distutils: language = c++
+
+from cpython cimport Py_buffer
+from libcpp.vector cimport vector
+
+
+cdef class Matrix:
+
+    cdef int view_count
+
+    cdef Py_ssize_t ncols
+    cdef vector[float] v
+    # ...
+
+    def __cinit__(self, Py_ssize_t ncols):
+        self.ncols = ncols
+        self.view_count = 0
+
+    def add_row(self):
+        if self.view_count > 0:
+            raise ValueError("can't add row while being viewed")
+        self.v.resize(self.v.size() + self.ncols)
+
+    def __getbuffer__(self, Py_buffer *buffer, int flags):
+        # ... as before
+
+        self.view_count += 1
+
+    def __releasebuffer__(self, Py_buffer *buffer):
+        self.view_count -= 1