Inline function definitions in pxd files

Cython/Compiler/ModuleNode.py

@@ -757,8 +757,8 @@ class ModuleNode(Nodes.Node, Nodes.BlockNode):
     
     def generate_cfunction_predeclarations(self, env, code, definition):
         for entry in env.cfunc_entries:
-            if not entry.in_cinclude and (definition
-                    or entry.defined_in_pxd or entry.visibility == 'extern'):
+            if entry.inline_func_in_pxd or (not entry.in_cinclude and (definition
+                    or entry.defined_in_pxd or entry.visibility == 'extern')):
                 if entry.visibility in ('public', 'extern'):
                     dll_linkage = "DL_EXPORT"
                 else:

Cython/Compiler/Nodes.py

@@ -1212,9 +1212,12 @@ class CFuncDefNode(FuncDefNode):
     #  type          CFuncType
     #  py_func       wrapper for calling from Python
     #  overridable   whether or not this is a cpdef function
+    #  inline_in_pxd whether this is an inline function in a pxd file
     
     child_attrs = ["base_type", "declarator", "body", "py_func"]
 
+    inline_in_pxd = False
+
     def unqualified_name(self):
         return self.entry.name
         
@@ -1251,6 +1254,7 @@ class CFuncDefNode(FuncDefNode):
             cname = cname, visibility = self.visibility,
             defining = self.body is not None,
             api = self.api, modifiers = self.modifiers)
+        self.entry.inline_func_in_pxd = self.inline_in_pxd
         self.return_type = type.return_type
         
         if self.overridable:

Cython/Compiler/ParseTreeTransforms.py

@@ -212,8 +212,12 @@ class PxdPostParse(CythonTransform):
 
     - "def" functions are let through only if they fill the
     getbuffer/releasebuffer slots
+    
+    - cdef functions are let through only if they are on the
+    top level and are declared "inline"
     """
-    ERR_FUNCDEF_NOT_ALLOWED = 'function definition not allowed here'
+    ERR_INLINE_ONLY = "function definition in pxd file must be declared 'cdef inline'"
+    ERR_NOGO_WITH_INLINE = "inline function definition in pxd file cannot be '%s'"
 
     def __call__(self, node):
         self.scope_type = 'pxd'
@@ -229,17 +233,26 @@ class PxdPostParse(CythonTransform):
     def visit_FuncDefNode(self, node):
         # FuncDefNode always come with an implementation (without
         # an imp they are CVarDefNodes..)
-        ok = False
+        err = self.ERR_INLINE_ONLY
 
         if (isinstance(node, DefNode) and self.scope_type == 'cclass'
             and node.name in ('__getbuffer__', '__releasebuffer__')):
-            ok = True
+            err = None # allow these slots
             
         if isinstance(node, CFuncDefNode):
-            ok = True
+            if u'inline' in node.modifiers and self.scope_type == 'pxd':
+                node.inline_in_pxd = True
+                if node.visibility != 'private':
+                    err = self.ERR_NOGO_WITH_INLINE % node.visibility
+                elif node.api:
+                    err = self.ERR_NOGO_WITH_INLINE % 'api'
+                else:
+                    err = None # allow inline function
+            else:
+                err = None
                 for stat in node.body.stats:
                     if not isinstance(stat, CVarDefNode):
-                    ok = False
+                        err = self.ERR_INLINE_ONLY
                         break
                 node = CVarDefNode(node.pos, 
                                    visibility = node.visibility,
@@ -249,10 +262,8 @@ class PxdPostParse(CythonTransform):
                                    api = node.api,
                                    overridable = node.overridable, 
                                    pxd_locals = node.body.stats)
-
-        if not ok:
-            self.context.nonfatal_error(PostParseError(node.pos,
-                self.ERR_FUNCDEF_NOT_ALLOWED))
+        if err:
+            self.context.nonfatal_error(PostParseError(node.pos, err))
             return None
         else:
             return node

Cython/Compiler/Symtab.py

@@ -97,7 +97,10 @@ class Entry:
     # utility_code     string     Utility code needed when this entry is used
     #
     # buffer_aux      BufferAux or None  Extra information needed for buffer variables
+    # inline_func_in_pxd boolean  Hacky special case for inline function in pxd file.
+    #                             Ideally this should not be necesarry.
 
+    inline_func_in_pxd = False
     borrowed = 0
     init = ""
     visibility = 'private'

tests/errors/e_func_in_pxd.pyx

 cimport e_func_in_pxd_support
 
 _ERRORS = u"""
-1:5: function definition not allowed here
+1:5: function definition in pxd file must be declared 'cdef inline'
+4:5: inline function definition in pxd file cannot be 'public'
+7:5: inline function definition in pxd file cannot be 'api'
 """

tests/errors/e_func_in_pxd_support.pxd

 cdef foo():
     return 1
+
+cdef public inline foo2():
+    return 1
+
+cdef api inline foo3():
+    return 1

tests/run/inlinepxd.pxd

+
+cdef inline int my_add(int a, int b):
+    return a + b

tests/run/inlinepxd.pyx

+"""
+>>> f()
+3
+>>> g()
+6
+>>> h()
+6
+"""
+
+cimport inlinepxd_support
+from inlinepxd_support cimport my_add as my_add3
+
+def f():
+    return my_add(1, 2)
+
+def g():
+    return inlinepxd_support.my_add(1, 2, 3)
+
+def h():
+    return my_add3(1, 2, 3)

tests/run/inlinepxd_support.pxd

+
+cdef inline int my_add(int a, int b, int c):
+    return a + b + c