Issue #28496: Mark up constants 0, 1 and -1 that denote return values or
special input values as literal text.
diff --git a/Doc/c-api/slice.rst b/Doc/c-api/slice.rst
index e157df2..a825164 100644
--- a/Doc/c-api/slice.rst
+++ b/Doc/c-api/slice.rst
@@ -32,9 +32,9 @@
    assuming a sequence of length *length*. Treats indices greater than
    *length* as errors.
 
-   Returns 0 on success and -1 on error with no exception set (unless one of
+   Returns ``0`` on success and ``-1`` on error with no exception set (unless one of
    the indices was not :const:`None` and failed to be converted to an integer,
-   in which case -1 is returned with an exception set).
+   in which case ``-1`` is returned with an exception set).
 
    You probably do not want to use this function.
 
@@ -51,7 +51,7 @@
    of bounds indices are clipped in a manner consistent with the handling of
    normal slices.
 
-   Returns 0 on success and -1 on error with exception set.
+   Returns ``0`` on success and ``-1`` on error with exception set.
 
    .. versionchanged:: 3.2
       The parameter type for the *slice* parameter was ``PySliceObject*``