Merge pull request #66 from markflorisson88/fusedmerge

Fused Types

Cython/Compiler/AnalysedTreeTransforms.py

 from Cython.Compiler.Visitor import VisitorTransform, ScopeTrackingTransform, TreeVisitor
-from Nodes import StatListNode, SingleAssignmentNode, CFuncDefNode
+from Nodes import StatListNode, SingleAssignmentNode, CFuncDefNode, DefNode
 from ExprNodes import DictNode, DictItemNode, NameNode, UnicodeNode, NoneNode, \
                       ExprNode, AttributeNode, ModuleRefNode, DocstringRefNode
 from PyrexTypes import py_object_type
@@ -63,7 +63,7 @@ class AutoTestDictTransform(ScopeTrackingTransform):
         return node
 
     def visit_FuncDefNode(self, node):
-        if not node.doc:
+        if not node.doc or (isinstance(node, DefNode) and node.fused_py_func):
             return node
         if not self.cdef_docstrings:
             if isinstance(node, CFuncDefNode) and not node.py_func:

Cython/Compiler/Code.py

@@ -263,7 +263,6 @@ class UtilityCode(UtilityCodeBase):
     def get_tree(self):
         pass
 
-
     def specialize(self, pyrex_type=None, tempita=False, **data):
         # Dicts aren't hashable...
         if pyrex_type is not None:

Cython/Compiler/CythonScope.py

@@ -18,6 +18,13 @@ class CythonScope(ModuleScope):
         # The Main.Context object
         self.context = context
 
+        for fused_type in (cy_integral_type, cy_floating_type, cy_numeric_type):
+            entry = self.declare_typedef(fused_type.name,
+                                         fused_type,
+                                         None,
+                                         cname='<error>')
+            entry.in_cinclude = True
+
     def lookup_type(self, name):
         # This function should go away when types are all first-level objects.
         type = parse_basic_type(name)
@@ -114,6 +121,7 @@ class CythonScope(ModuleScope):
 
         view_utility_scope = MemoryView.view_utility_code.declare_in_scope(
                                                 viewscope, cython_scope=self)
+
         # MemoryView.memview_fromslice_utility_code.from_scope = view_utility_scope
         # MemoryView.memview_fromslice_utility_code.declare_in_scope(viewscope)
 
@@ -124,7 +132,6 @@ def create_cython_scope(context):
     # it across different contexts)
     return CythonScope(context)
 
-
 # Load test utilities for the cython scope
 
 def load_testscope_utility(cy_util_name, **kwargs):

Cython/Compiler/MemoryView.py

@@ -130,9 +130,6 @@ def get_buf_flags(specs):
         return memview_strided_access
 
 
-def use_cython_array(env):
-    env.use_utility_code(cython_array_utility_code)
-
 def src_conforms_to_dst(src, dst):
     '''
     returns True if src conforms to dst, False otherwise.
@@ -171,15 +168,18 @@ def valid_memslice_dtype(dtype):
 
     return (
         dtype.is_error or
+        # Pointers are not valid (yet)
+        # (dtype.is_ptr and valid_memslice_dtype(dtype.base_type)) or
         dtype.is_numeric or
         dtype.is_struct or
         dtype.is_pyobject or
+        dtype.is_fused or # accept this as it will be replaced by specializations later
         (dtype.is_typedef and valid_memslice_dtype(dtype.typedef_base_type))
     )
 
 def validate_memslice_dtype(pos, dtype):
     if not valid_memslice_dtype(dtype):
-        error(pos, "Invalid base type for memoryview slice")
+        error(pos, "Invalid base type for memoryview slice: %s" % dtype)
 
 
 class MemoryViewSliceBufferEntry(Buffer.BufferEntry):
@@ -936,6 +936,10 @@ def load_memview_c_utility(util_code_name, context=None, **kwargs):
     return UtilityCode.load(util_code_name, "MemoryView_C.c",
                             context=context, **kwargs)
 
+def use_cython_array_utility_code(env):
+    env.global_scope().context.cython_scope.lookup('array_cwrapper').used = True
+    env.use_utility_code(cython_array_utility_code)
+
 context = {
     'memview_struct_name': memview_objstruct_cname,
     'max_dims': Options.buffer_max_dims,

Cython/Compiler/ModuleNode.py

@@ -591,6 +591,10 @@ class ModuleNode(Nodes.Node, Nodes.BlockNode):
           PyCode_New(a, k, l, s, f, code, c, n, v, fv, cell, fn, name, fline, lnos)
 #endif
 
+#if PY_MAJOR_VERSION < 3 && PY_MINOR_VERSION < 6
+  #define PyUnicode_FromString(s) PyUnicode_Decode(s, strlen(s), "UTF-8", "strict")
+#endif
+
 #if PY_MAJOR_VERSION >= 3
   #define Py_TPFLAGS_CHECKTYPES 0
   #define Py_TPFLAGS_HAVE_INDEX 0
@@ -985,6 +989,9 @@ class ModuleNode(Nodes.Node, Nodes.BlockNode):
         # Generate struct declaration for an extension type's vtable.
         type = entry.type
         scope = type.scope
+
+        self.specialize_fused_types(scope)
+
         if type.vtabstruct_cname:
             code.putln("")
             code.putln(
@@ -1128,6 +1135,7 @@ class ModuleNode(Nodes.Node, Nodes.BlockNode):
 
     def generate_cfunction_declarations(self, env, code, definition):
         for entry in env.cfunc_entries:
+            if entry.used:
                 generate_cfunction_declaration(entry, env, code, definition)
 
     def generate_variable_definitions(self, env, code):
@@ -1800,6 +1808,7 @@ class ModuleNode(Nodes.Node, Nodes.BlockNode):
             "static PyMethodDef %s[] = {" %
                 env.method_table_cname)
         for entry in env.pyfunc_entries:
+            if not entry.fused_cfunction:
                 code.put_pymethoddef(entry, ",")
         code.putln(
                 "{0, 0, 0, 0}")
@@ -1928,6 +1937,10 @@ class ModuleNode(Nodes.Node, Nodes.BlockNode):
         code.putln("if (__Pyx_CyFunction_init() < 0) %s" % code.error_goto(self.pos))
         code.putln("#endif")
 
+        code.putln("#ifdef __Pyx_FusedFunction_USED")
+        code.putln("if (__pyx_FusedFunction_init() < 0) %s" % code.error_goto(self.pos))
+        code.putln("#endif")
+
         code.putln("/*--- Library function declarations ---*/")
         env.generate_library_function_declarations(code)
 
@@ -1983,6 +1996,7 @@ class ModuleNode(Nodes.Node, Nodes.BlockNode):
 
         code.putln("/*--- Function import code ---*/")
         for module in imported_modules:
+            self.specialize_fused_types(module)
             self.generate_c_function_import_code_for_module(module, env, code)
 
         code.putln("/*--- Execution code ---*/")
@@ -2200,6 +2214,18 @@ class ModuleNode(Nodes.Node, Nodes.BlockNode):
             if entry.defined_in_pxd:
                 self.generate_type_import_code(env, entry.type, entry.pos, code)
 
+    def specialize_fused_types(self, pxd_env):
+        """
+        If fused c(p)def functions are defined in an imported pxd, but not
+        used in this implementation file, we still have fused entries and
+        not specialized ones. This method replaces any fused entries with their
+        specialized ones.
+        """
+        for entry in pxd_env.cfunc_entries[:]:
+            if entry.type.is_fused:
+                # This call modifies the cfunc_entries in-place
+                entry.type.get_all_specific_function_types()
+
     def generate_c_variable_import_code_for_module(self, module, env, code):
         # Generate import code for all exported C functions in a cimported module.
         entries = []
@@ -2232,7 +2258,7 @@ class ModuleNode(Nodes.Node, Nodes.BlockNode):
         # Generate import code for all exported C functions in a cimported module.
         entries = []
         for entry in module.cfunc_entries:
-            if entry.defined_in_pxd:
+            if entry.defined_in_pxd and entry.used:
                 entries.append(entry)
         if entries:
             env.use_utility_code(import_module_utility_code)
@@ -2441,7 +2467,7 @@ class ModuleNode(Nodes.Node, Nodes.BlockNode):
 
 def generate_cfunction_declaration(entry, env, code, definition):
     from_cy_utility = entry.used and entry.utility_code_definition
-    if entry.inline_func_in_pxd or (not entry.in_cinclude and (definition
+    if entry.used and entry.inline_func_in_pxd or (not entry.in_cinclude and (definition
             or entry.defined_in_pxd or entry.visibility == 'extern' or from_cy_utility)):
         if entry.visibility == 'extern':
             storage_class = "%s " % Naming.extern_c_macro

Cython/Compiler/Naming.py

@@ -92,6 +92,7 @@ enc_scope_cname  = pyrex_prefix + "enc_scope"
 frame_cname      = pyrex_prefix + "frame"
 frame_code_cname = pyrex_prefix + "frame_code"
 binding_cfunc    = pyrex_prefix + "binding_PyCFunctionType"
+fused_func_prefix = pyrex_prefix + 'fuse_'
 quick_temp_cname = pyrex_prefix + "temp" # temp variable for quick'n'dirty temping
 
 genexpr_id_ref = 'genexpr'

Cython/Compiler/Optimize.py

@@ -2992,8 +2992,18 @@ class ConstantFolding(Visitor.VisitorTransform, SkipDeclarations):
       literal nodes at each step.  Non-literal nodes are never merged
       into a single node.
     """
+
+    def __init__(self, reevaluate=False):
+        """
+        The reevaluate argument specifies whether constant values that were
+        previously computed should be recomputed.
+        """
+        super(ConstantFolding, self).__init__()
+        self.reevaluate = reevaluate
+
     def _calculate_const(self, node):
-        if node.constant_result is not ExprNodes.constant_value_not_set:
+        if (not self.reevaluate and
+                node.constant_result is not ExprNodes.constant_value_not_set):
             return
 
         # make sure we always set the value

Cython/Compiler/ParseTreeTransforms.py

@@ -629,8 +629,9 @@ class InterpretCompilerDirectives(CythonTransform, SkipDeclarations):
         'operator.comma'        : ExprNodes.c_binop_constructor(','),
     }
 
-    special_methods = set(['declare', 'union', 'struct', 'typedef', 'sizeof',
-                                  'cast', 'pointer', 'compiled', 'NULL', 'parallel'])
+    special_methods = set(['declare', 'union', 'struct', 'typedef',
+                           'sizeof', 'cast', 'pointer', 'compiled',
+                           'NULL', 'fused_type', 'parallel'])
     special_methods.update(unop_method_nodes.keys())
 
     valid_parallel_directives = set([
@@ -1381,10 +1382,13 @@ if VALUE is not None:
     count += 1
     """)
 
+    fused_function = None
+
     def __call__(self, root):
         self.env_stack = [root.scope]
         # needed to determine if a cdef var is declared after it's used.
         self.seen_vars_stack = []
+        self.fused_error_funcs = set()
         return super(AnalyseDeclarationsTransform, self).__call__(root)
 
     def visit_NameNode(self, node):
@@ -1424,9 +1428,20 @@ if VALUE is not None:
         return node
 
     def visit_FuncDefNode(self, node):
+        """
+        Analyse a function and its body, as that hasn't happend yet. Also
+        analyse the directive_locals set by @cython.locals(). Then, if we are
+        a function with fused arguments, replace the function (after it has
+        declared itself in the symbol table!) with a FusedCFuncDefNode, and
+        analyse its children (which are in turn normal functions). If we're a
+        normal function, just analyse the body of the function.
+        """
+        env = self.env_stack[-1]
+
         self.seen_vars_stack.append(set())
         lenv = node.local_scope
         node.declare_arguments(lenv)
+
         for var, type_node in node.directive_locals.items():
             if not lenv.lookup_here(var):   # don't redeclare args
                 type = type_node.analyse_as_type(lenv)
@@ -1434,6 +1449,37 @@ if VALUE is not None:
                     lenv.declare_var(var, type, type_node.pos)
                 else:
                     error(type_node.pos, "Not a type")
+
+        if node.is_generator and node.has_fused_arguments:
+            node.has_fused_arguments = False
+            error(node.pos, "Fused generators not supported")
+            node.gbody = Nodes.StatListNode(node.pos,
+                                            stats=[],
+                                            body=Nodes.PassStatNode(node.pos))
+
+        if node.has_fused_arguments:
+            if self.fused_function:
+                if self.fused_function not in self.fused_error_funcs:
+                    error(node.pos, "Cannot nest fused functions")
+
+                self.fused_error_funcs.add(self.fused_function)
+                # env.declare_var(node.name, PyrexTypes.py_object_type, node.pos)
+                node = Nodes.SingleAssignmentNode(
+                    node.pos,
+                    lhs=ExprNodes.NameNode(node.pos, name=node.name),
+                    rhs=ExprNodes.NoneNode(node.pos))
+                node.analyse_declarations(env)
+                return node
+
+            node = Nodes.FusedCFuncDefNode(node, env)
+
+            self.fused_function = node
+            self.visitchildren(node)
+            self.fused_function = None
+
+            if node.py_func:
+                node.stats.insert(0, node.py_func)
+        else:
             node.body.analyse_declarations(lenv)
 
             if lenv.nogil and lenv.has_with_gil_block:
@@ -1450,6 +1496,7 @@ if VALUE is not None:
             self.env_stack.append(lenv)
             self.visitchildren(node)
             self.env_stack.pop()
+
         self.seen_vars_stack.pop()
         return node
 
@@ -1628,15 +1675,18 @@ if VALUE is not None:
 class AnalyseExpressionsTransform(CythonTransform):
 
     def visit_ModuleNode(self, node):
+        self.env_stack = [node.scope]
         node.scope.infer_types()
         node.body.analyse_expressions(node.scope)
         self.visitchildren(node)
         return node
 
     def visit_FuncDefNode(self, node):
+        self.env_stack.append(node.local_scope)
         node.local_scope.infer_types()
         node.body.analyse_expressions(node.local_scope)
         self.visitchildren(node)
+        self.env_stack.pop()
         return node
 
     def visit_ScopedExprNode(self, node):
@@ -1646,6 +1696,24 @@ class AnalyseExpressionsTransform(CythonTransform):
         self.visitchildren(node)
         return node
 
+    def visit_IndexNode(self, node):
+        """
+        Replace index nodes used to specialize cdef functions with fused
+        argument types with the Attribute- or NameNode referring to the
+        function. We then need to copy over the specialization properties to
+        the attribute or name node.
+
+        Because the indexing might be a Python indexing operation on a fused
+        function, or (usually) a Cython indexing operation, we need to
+        re-analyse the types.
+        """
+        self.visit_Node(node)
+
+        if node.is_fused_index and node.type is not PyrexTypes.error_type:
+            node = node.base
+
+        return node
+
 
 class ExpandInplaceOperators(EnvTransform):
 
@@ -2084,6 +2152,10 @@ class CreateClosureClasses(CythonTransform):
         target_module_scope.check_c_class(func_scope.scope_class)
 
     def visit_LambdaNode(self, node):
+        if not isinstance(node.def_node, Nodes.DefNode):
+            # fused function, an error has been previously issued
+            return node
+
         was_in_lambda = self.in_lambda
         self.in_lambda = True
         self.create_class_from_scope(node.def_node, self.module_scope, node)
@@ -2396,6 +2468,95 @@ class TransformBuiltinMethods(EnvTransform):
         return node
 
 
+class ReplaceFusedTypeChecks(VisitorTransform):
+    """
+    This is not a transform in the pipeline. It is invoked on the specific
+    versions of a cdef function with fused argument types. It filters out any
+    type branches that don't match. e.g.
+
+        if fused_t is mytype:
+            ...
+        elif fused_t in other_fused_type:
+            ...
+    """
+
+    # Defer the import until now to avoid circularity...
+    from Cython.Compiler import Optimize
+    transform = Optimize.ConstantFolding(reevaluate=True)
+
+    def __init__(self, local_scope):
+        super(ReplaceFusedTypeChecks, self).__init__()
+        self.local_scope = local_scope
+
+    def visit_IfStatNode(self, node):
+        """
+        Filters out any if clauses with false compile time type check
+        expression.
+        """
+        self.visitchildren(node)
+        return self.transform(node)
+
+    def visit_PrimaryCmpNode(self, node):
+        type1 = node.operand1.analyse_as_type(self.local_scope)
+        type2 = node.operand2.analyse_as_type(self.local_scope)
+
+        if type1 and type2:
+            false_node = ExprNodes.BoolNode(node.pos, value=False)
+            true_node = ExprNodes.BoolNode(node.pos, value=True)
+
+            type1 = self.specialize_type(type1, node.operand1.pos)
+            op = node.operator
+
+            if op in ('is', 'is_not', '==', '!='):
+                type2 = self.specialize_type(type2, node.operand2.pos)
+
+                is_same = type1.same_as(type2)
+                eq = op in ('is', '==')
+
+                if (is_same and eq) or (not is_same and not eq):
+                    return true_node
+
+            elif op in ('in', 'not_in'):
+                # We have to do an instance check directly, as operand2
+                # needs to be a fused type and not a type with a subtype
+                # that is fused. First unpack the typedef
+                if isinstance(type2, PyrexTypes.CTypedefType):
+                    type2 = type2.typedef_base_type
+
+                if type1.is_fused:
+                    error(node.operand1.pos, "Type is fused")
+                elif not type2.is_fused:
+                    error(node.operand2.pos,
+                          "Can only use 'in' or 'not in' on a fused type")
+                else:
+                    types = PyrexTypes.get_specialized_types(type2)
+
+                    for specific_type in types:
+                        if type1.same_as(specific_type):
+                            if op == 'in':
+                                return true_node
+                            else:
+                                return false_node
+
+                    if op == 'not_in':
+                        return true_node
+
+            return false_node
+
+        return node
+
+    def specialize_type(self, type, pos):
+        try:
+            return type.specialize(self.local_scope.fused_to_specific)
+        except KeyError:
+            error(pos, "Type is not specific")
+            return type
+
+    def visit_Node(self, node):
+        self.visitchildren(node)
+        return node
+
+
 class DebugTransform(CythonTransform):
     """
     Write debug information for this Cython module.

Cython/Compiler/Parsing.pxd

@@ -134,9 +134,10 @@ cdef p_buffer_or_template(PyrexScanner s, base_type_node, templates)
 cdef is_memoryviewslice_access(PyrexScanner s)
 cdef p_memoryviewslice_access(PyrexScanner s, base_type_node)
 cdef bint looking_at_name(PyrexScanner s) except -2
-cdef bint looking_at_expr(PyrexScanner s) except -2
+cdef object looking_at_expr(PyrexScanner s)# except -2
 cdef bint looking_at_base_type(PyrexScanner s) except -2
 cdef bint looking_at_dotted_name(PyrexScanner s) except -2
+cdef bint looking_at_call(PyrexScanner s) except -2
 cdef p_sign_and_longness(PyrexScanner s)
 cdef p_opt_cname(PyrexScanner s)
 cpdef p_c_declarator(PyrexScanner s, ctx = *, bint empty = *, bint is_type = *, bint cmethod_flag = *,
@@ -161,6 +162,7 @@ cdef p_c_enum_definition(PyrexScanner s, pos, ctx)
 cdef p_c_enum_line(PyrexScanner s, ctx, list items)
 cdef p_c_enum_item(PyrexScanner s, ctx, list items)
 cdef p_c_struct_or_union_definition(PyrexScanner s, pos, ctx)
+cdef p_fused_definition(PyrexScanner s, pos, ctx)
 cdef p_visibility(PyrexScanner s, prev_visibility)
 cdef p_c_modifiers(PyrexScanner s)
 cdef p_c_func_or_var_declaration(PyrexScanner s, pos, ctx)

Cython/Compiler/Parsing.py

@@ -2121,10 +2121,12 @@ def looking_at_expr(s):
         name = s.systring
         dotted_path = []
         s.next()
+
         while s.sy == '.':
             s.next()
             dotted_path.append(s.systring)
             s.expect('IDENT')
+
         saved = s.sy, s.systring
         if s.sy == 'IDENT':
             is_type = True
@@ -2140,12 +2142,14 @@ def looking_at_expr(s):
             s.next()
             is_type = s.sy == ']'
             s.put_back(*saved)
+
         dotted_path.reverse()
         for p in dotted_path:
             s.put_back('IDENT', p)
             s.put_back('.', '.')
+
         s.put_back('IDENT', name)
-        return not is_type
+        return not is_type and saved[0]
     else:
         return True
 
@@ -2163,6 +2167,17 @@ def looking_at_dotted_name(s):
     else:
         return 0
 
+def looking_at_call(s):
+    "See if we're looking at a.b.c("
+    # Don't mess up the original position, so save and restore it.
+    # Unfortunately there's no good way to handle this, as a subsequent call
+    # to next() will not advance the position until it reads a new token.
+    position = s.start_line, s.start_col
+    result = looking_at_expr(s) == u'('
+    if not result:
+        s.start_line, s.start_col = position
+    return result
+
 basic_c_type_names = ("void", "char", "int", "float", "double", "bint")
 
 special_basic_c_types = {
@@ -2179,6 +2194,8 @@ sign_and_longness_words = ("short", "long", "signed", "unsigned")
 base_type_start_words = \
     basic_c_type_names + sign_and_longness_words + tuple(special_basic_c_types)
 
+struct_enum_union = ("struct", "union", "enum", "packed")
+
 def p_sign_and_longness(s):
     signed = 1
     longness = 0
@@ -2485,15 +2502,14 @@ def p_cdef_statement(s, ctx):
         if ctx.visibility != 'extern':
             error(pos, "C++ classes need to be declared extern")
         return p_cpp_class_definition(s, pos, ctx)
-    elif s.sy == 'IDENT' and s.systring in ("struct", "union", "enum", "packed"):
+    elif s.sy == 'IDENT' and s.systring in struct_enum_union:
         if ctx.level not in ('module', 'module_pxd'):
             error(pos, "C struct/union/enum definition not allowed here")
         if ctx.overridable:
             error(pos, "C struct/union/enum cannot be declared cpdef")
-        if s.systring == "enum":
-            return p_c_enum_definition(s, pos, ctx)
-        else:
-            return p_c_struct_or_union_definition(s, pos, ctx)
+        return p_struct_enum(s, pos, ctx)
+    elif s.sy == 'IDENT' and s.systring == 'fused':
+        return p_fused_definition(s, pos, ctx)
     else:
         return p_c_func_or_var_declaration(s, pos, ctx)
 
@@ -2610,6 +2626,46 @@ def p_c_struct_or_union_definition(s, pos, ctx):
         typedef_flag = ctx.typedef_flag, visibility = ctx.visibility,
         api = ctx.api, in_pxd = ctx.level == 'module_pxd', packed = packed)
 
+def p_fused_definition(s, pos, ctx):
+    """
+    c(type)def fused my_fused_type:
+        ...
+    """
+    # s.systring == 'fused'
+
+    if ctx.level not in ('module', 'module_pxd'):
+        error(pos, "Fused type definition not allowed here")
+
+    s.next()
+    name = p_ident(s)
+
+    s.expect(":")
+    s.expect_newline()
+    s.expect_indent()
+
+    types = []
+    while s.sy != 'DEDENT':
+        if s.sy != 'pass':
+            #types.append(p_c_declarator(s))
+            types.append(p_c_base_type(s)) #, nonempty=1))
+        else:
+            s.next()
+
+        s.expect_newline()
+
+    s.expect_dedent()
+
+    if not types:
+        error(pos, "Need at least one type")
+
+    return Nodes.FusedTypeNode(pos, name=name, types=types)
+
+def p_struct_enum(s, pos, ctx):
+    if s.systring == 'enum':
+        return p_c_enum_definition(s, pos, ctx)
+    else:
+        return p_c_struct_or_union_definition(s, pos, ctx)
+
 def p_visibility(s, prev_visibility):
     pos = s.position()
     visibility = prev_visibility
@@ -2680,11 +2736,10 @@ def p_ctypedef_statement(s, ctx):
         ctx.api = 1
     if s.sy == 'class':
         return p_c_class_definition(s, pos, ctx)
-    elif s.sy == 'IDENT' and s.systring in ('packed', 'struct', 'union', 'enum'):
-        if s.systring == 'enum':
-            return p_c_enum_definition(s, pos, ctx)
-        else:
-            return p_c_struct_or_union_definition(s, pos, ctx)
+    elif s.sy == 'IDENT' and s.systring in struct_enum_union:
+        return p_struct_enum(s, pos, ctx)
+    elif s.sy == 'IDENT' and s.systring == 'fused':
+        return p_fused_definition(s, pos, ctx)
     else:
         base_type = p_c_base_type(s, nonempty = 1)
         declarator = p_c_declarator(s, ctx, is_type = 1, nonempty = 1)

Cython/Compiler/Pipeline.py

@@ -62,17 +62,25 @@ def inject_pxd_code_stage_factory(context):
         return module_node
     return inject_pxd_code_stage
 
-def use_utility_code_definitions(scope, target):
+def use_utility_code_definitions(scope, target, seen=None):
+    if seen is None:
+        seen = set()
+
     for entry in scope.entries.itervalues():
+        if entry in seen:
+            continue
+
+        seen.add(entry)
         if entry.used and entry.utility_code_definition:
             target.use_utility_code(entry.utility_code_definition)
             for required_utility in entry.utility_code_definition.requires:
                 target.use_utility_code(required_utility)
         elif entry.as_module:
-            use_utility_code_definitions(entry.as_module, target)
+            use_utility_code_definitions(entry.as_module, target, seen)
 
 def inject_utility_code_stage_factory(context):
     def inject_utility_code_stage(module_node):
+        use_utility_code_definitions(context.cython_scope, module_node.scope)
         added = []
         # Note: the list might be extended inside the loop (if some utility code
         # pulls in other utility code, explicitly or implicitly)

Cython/Compiler/StringEncoding.py

@@ -115,6 +115,9 @@ class EncodedString(_unicode):
     # otherwise
     encoding = None
 
+    def __deepcopy__(self, memo):
+        return self
+
     def byteencode(self):
         assert self.encoding is not None
         return self.encode(self.encoding)
@@ -131,6 +134,9 @@ class BytesLiteral(_bytes):
     # bytes subclass that is compatible with EncodedString
     encoding = None
 
+    def __deepcopy__(self, memo):
+        return self
+
     def byteencode(self):
         if IS_PYTHON3:
             return _bytes(self)

Cython/Compiler/Symtab.py

@@ -180,6 +180,7 @@ class Entry(object):
     buffer_aux = None
     prev_entry = None
     might_overflow = 0
+    fused_cfunction = None
     utility_code_definition = None
     in_with_gil_block = 0
     from_cython_utility_code = None
@@ -250,6 +251,7 @@ class Scope(object):
     scope_prefix = ""
     in_cinclude = 0
     nogil = 0
+    fused_to_specific = None
 
     def __init__(self, name, outer_scope, parent_scope):
         # The outer_scope is the next scope in the lookup chain.
@@ -286,6 +288,9 @@ class Scope(object):
         self.return_type = None
         self.id_counters = {}
 
+    def __deepcopy__(self, memo):
+        return self
+
     def merge_in(self, other, merge_unused=True):
         # Use with care...
         entries = [(name, entry)
@@ -415,6 +420,9 @@ class Scope(object):
         entry.api = api
         if defining:
             self.type_entries.append(entry)
+
+        type.entry = entry
+
         # here we would set as_variable to an object representing this type
         return entry
 
@@ -670,6 +678,7 @@ class Scope(object):
         if modifiers:
             entry.func_modifiers = modifiers
         entry.utility_code = utility_code
+        type.entry = entry
         return entry
 
     def add_cfunction(self, name, type, pos, cname, visibility, modifiers):
@@ -726,6 +735,8 @@ class Scope(object):
     def lookup_type(self, name):
         entry = self.lookup(name)
         if entry and entry.is_type:
+            if entry.type.is_fused and self.fused_to_specific:
+                return entry.type.specialize(self.fused_to_specific)
             return entry.type
 
     def lookup_operator(self, operator, operands):
@@ -770,6 +781,7 @@ class Scope(object):
     def add_include_file(self, filename):
         self.outer_scope.add_include_file(filename)
 
+
 class PreImportScope(Scope):
 
     namespace_cname = Naming.preimport_cname
@@ -1562,6 +1574,7 @@ class ClosureScope(LocalScope):
     def declare_pyfunction(self, name, pos, allow_redefine=False):
         return LocalScope.declare_pyfunction(self, name, pos, allow_redefine, visibility='private')
 
+
 class StructOrUnionScope(Scope):
     #  Namespace of a C struct or union.
 
@@ -1850,12 +1863,16 @@ class CClassScope(ClassScope):
         if defining:
             entry.func_cname = self.mangle(Naming.func_prefix, name)
         entry.utility_code = utility_code
+        type.entry = entry
+
         if u'inline' in modifiers:
             entry.is_inline_cmethod = True
+
         if (self.parent_type.is_final_type or entry.is_inline_cmethod or
             self.directives.get('final')):
             entry.is_final_cmethod = True
             entry.final_func_cname = entry.func_cname
+
         return entry
 
     def add_cfunction(self, name, type, pos, cname, visibility, modifiers):
@@ -1898,12 +1915,21 @@ class CClassScope(ClassScope):
         # to work with this type.
         def adapt(cname):
             return "%s.%s" % (Naming.obj_base_cname, base_entry.cname)
-        for base_entry in \
-                base_scope.inherited_var_entries + base_scope.var_entries:
+
+        entries = base_scope.inherited_var_entries + base_scope.var_entries
+        for base_entry in entries:
                 entry = self.declare(base_entry.name, adapt(base_entry.cname),
                     base_entry.type, None, 'private')
                 entry.is_variable = 1
                 self.inherited_var_entries.append(entry)
+
+        # If the class defined in a pxd, specific entries have not been added.
+        # Ensure now that the parent (base) scope has specific entries
+        # Iterate over a copy as get_all_specific_function_types() will mutate
+        for base_entry in base_scope.cfunc_entries[:]:
+            if base_entry.type.is_fused:
+                base_entry.type.get_all_specific_function_types()
+
         for base_entry in base_scope.cfunc_entries:
             cname = base_entry.cname
             var_entry = base_entry.as_variable
@@ -1993,6 +2019,7 @@ class CppClassScope(Scope):
         if prev_entry:
             entry.overloaded_alternatives = prev_entry.all_alternatives()
         entry.utility_code = utility_code
+        type.entry = entry
         return entry
 
     def declare_inherited_cpp_attributes(self, base_scope):

Cython/Compiler/TypeInference.py

@@ -372,7 +372,7 @@ class SimpleAssignmentTypeInferer(object):
             while ready_to_infer:
                 entry = ready_to_infer.pop()
                 types = [expr.infer_type(scope) for expr in entry.assignments]
-                if types:
+                if types and Utils.all(types):
                     entry.type = spanning_type(types, entry.might_overflow)
                 else:
                     # FIXME: raise a warning?

Cython/Distutils/build_ext.py

@@ -55,16 +55,6 @@ class Optimization(object):
 
 optimization = Optimization()
 
-try:
-    any
-except NameError:
-    def any(it):
-        for x in it:
-            if x:
-                return True
-
-        return False
-
 
 class build_ext(_build_ext.build_ext):
 
@@ -128,8 +118,8 @@ class build_ext(_build_ext.build_ext):
         # If --pyrex-gdb is in effect as a command line option or as option
         # of any Extension module, disable optimization for the C or C++
         # compiler.
-        if (self.pyrex_gdb or any([getattr(ext, 'pyrex_gdb', False)
-                                       for ext in self.extensions])):
+        if self.pyrex_gdb or [1 for ext in self.extensions
+                                     if getattr(ext, 'pyrex_gdb', False)]:
             optimization.disable_optimization()
 
         _build_ext.build_ext.run(self)

Cython/Shadow.py

@@ -66,7 +66,8 @@ def sizeof(arg):
     return 1
 
 def typeof(arg):
-    return type(arg)
+    return arg.__class__.__name__
+    # return type(arg)
 
 def address(arg):
     return pointer(type(arg))([arg])
@@ -138,6 +139,9 @@ class PointerType(CythonType):
         else:
             return not self._items and not value._items
 
+    def __repr__(self):
+        return "%s *" % (self._basetype,)
+
 class ArrayType(PointerType):
 
     def __init__(self):
@@ -221,22 +225,54 @@ def union(**members):
 
 class typedef(CythonType):
 
-    def __init__(self, type):
+    def __init__(self, type, name=None):
         self._basetype = type
+        self.name = name
 
     def __call__(self, *arg):
         value = cast(self._basetype, *arg)
         return value
 
+    def __repr__(self):
+        return self.name or str(self._basetype)
+
+class _FusedType(CythonType):
+    pass
+
+
+def fused_type(*args):
+    if not args:
+        raise TypeError("Expected at least one type as argument")
+
+    # Find the numeric type with biggest rank if all types are numeric
+    rank = -1
+    for type in args:
+        if type not in (py_int, py_long, py_float, py_complex):
+            break
+
+        if type_ordering.index(type) > rank:
+            result_type = type
+    else:
+        return result_type
+
+    # Not a simple numeric type, return a fused type instance. The result
+    # isn't really meant to be used, as we can't keep track of the context in
+    # pure-mode. Casting won't do anything in this case.
+    return _FusedType()
+
+
+def _specialized_from_args(signatures, args, kwargs):
+    "Perhaps this should be implemented in a TreeFragment in Cython code"
+    raise Exception("yet to be implemented")
 
 
-py_int = int
+py_int = typedef(int, "int")
 try:
-    py_long = long
+    py_long = typedef(long, "long")
 except NameError: # Py3
-    py_long = int
-py_float = float
-py_complex = complex
+    py_long = typedef(int, "long")
+py_float = typedef(float, "float")
+py_complex = typedef(complex, "double complex")
 
 
 # Predefined types
@@ -246,30 +282,43 @@ float_types = ['longdouble', 'double', 'float']
 complex_types = ['longdoublecomplex', 'doublecomplex', 'floatcomplex', 'complex']
 other_types = ['bint', 'void']
 
+to_repr = {
+    'longlong': 'long long',
+    'longdouble': 'long double',
+    'longdoublecomplex': 'long double complex',
+    'doublecomplex': 'double complex',
+    'floatcomplex': 'float complex',
+}.get
+
 gs = globals()
 
 for name in int_types:
-    gs[name] = typedef(py_int)
+    reprname = to_repr(name, name)
+    gs[name] = typedef(py_int, reprname)
     if name != 'Py_UNICODE' and not name.endswith('size_t'):
-        gs['u'+name] = typedef(py_int)
-        gs['s'+name] = typedef(py_int)
+        gs['u'+name] = typedef(py_int, "unsigned " + reprname)
+        gs['s'+name] = typedef(py_int, "signed " + reprname)
 
 for name in float_types:
-    gs[name] = typedef(py_float)
+    gs[name] = typedef(py_float, to_repr(name, name))
 
 for name in complex_types:
-    gs[name] = typedef(py_complex)
+    gs[name] = typedef(py_complex, to_repr(name, name))
 
-bint = typedef(bool)
-void = typedef(int)
+bint = typedef(bool, "bint")
+void = typedef(int, "void")
 
 for t in int_types + float_types + complex_types + other_types:
     for i in range(1, 4):
         gs["%s_%s" % ('p'*i, t)] = globals()[t]._pointer(i)
 
-void = typedef(None)
+void = typedef(None, "void")
 NULL = p_void(0)
 
+integral = floating = numeric = _FusedType()
+
+type_ordering = [py_int, py_long, py_float, py_complex]
+
 class CythonDotParallel(object):
     """
     The cython.parallel module.

Cython/Utils.py

@@ -216,3 +216,22 @@ def long_literal(value):
     if isinstance(value, basestring):
         value = str_to_number(value)
     return not -2**31 <= value < 2**31
+
+# all() and any() are new in 2.5
+try:
+    # Make sure to bind them on the module, as they will be accessed as
+    # attributes
+    all = all
+    any = any
+except NameError:
+    def all(items):
+        for item in items:
+            if not item:
+                return False
+        return True
+
+    def any(items):
+        for item in items:
+            if item:
+                return True
+        return False

docs/src/userguide/fusedtypes.rst

+.. highlight:: cython
+
+.. _fusedtypes:
+
+**************************
+Fused Types (Templates)
+**************************
+
+Fused types can be used to fuse multiple types into a single type, to allow a single
+algorithm to operate on values of multiple types. They are somewhat akin to templates
+or generics.
+
+.. Note:: Support is experimental and new in this release, there may be bugs!
+
+Declaring Fused Types
+=====================
+
+Fused types may be declared as follows::
+
+    cimport cython
+
+    ctypedef fused my_fused_type:
+        cython.p_int
+        cython.p_float
+
+This declares a new type called ``my_fused_type`` which is composed of a ``int *`` and a ``double *``.
+Alternatively, the declaration may be written as::
+
+    my_fused_type = cython.fused_type(cython.p_int, cython.p_float)
+
+Only names may be used for the constituent types, but they may be any (non-fused) type, including a typedef.
+i.e. one may write::
+
+    ctypedef double *doublep
+    my_fused_type = cython.fused_type(cython.p_int, doublep)
+
+Using Fused Types
+=================
+Fused types can be used to declare parameters of functions or methods::
+
+    cdef cfunc(my_fused_type arg1, my_fused_type arg2):
+        return cython.typeof(arg1) == cython.typeof(arg2)
+
+This declares a function with two parameters. The type of both parameters is either a pointer to an int,
+or a pointer to a float (according to the previous examples). So this function always True for every possible
+invocation. You are allowed to mix fused types however::
+
+    def func(A x, B y):
+        ...
+
+where ``A`` and ``B`` are different fused types. This will result in all combination of types.
+
+Note that specializations of only numeric types may not be very useful, as one can usually rely on
+promotion of types. This is not true for arrays, pointers and typed views of memory however.
+Indeed, one may write::
+
+    def myfunc(A[:, :] x):
+        ...
+
+    # and
+
+    cdef otherfunc(A *x):
+        ...
+
+
+Selecting Specializations
+=========================
+You can select a specialization (an instance of the function with specific or specialized (i.e.,
+non-fused) argument types) in two ways: either by indexing or by calling.
+
+Indexing
+--------
+You can index functions with types to get certain specializations, i.e.::
+
+    cfunc[cython.p_double](p1, p2)
+
+    # From Cython space
+    func[float, double](myfloat, mydouble)
+
+    # From Python space
+    func[cython.float, cython.double](myfloat, mydouble)
+
+If a fused type is used as a base type, this will mean that the base type is the fused type, so the
+base type is what needs to be specialized::
+
+    cdef myfunc(A *x):
+        ...
+
+    # Specialize using int, not int *
+    myfunc[int](myint)
+
+Calling
+-------
+A fused function can also be called with arguments, where the dispatch is figured out automatically::
+
+    cfunc(p1, p2)
+    func(myfloat, mydouble)
+
+For a ``cdef`` or ``cpdef`` function called from Cython this means that the specialization is figured
+out at compile time. For ``def`` functions the arguments are typechecked at runtime, and a best-effort
+approach is performed to figure out which specialization is needed. This means that this may result in
+a runtime ``TypeError`` if no specialization was found. A ``cpdef`` function is treated the same way as
+a ``def`` function if the type of the function is unknown (e.g. if it is external and there is no cimport
+for it).
+
+The automatic dispatching rules are typically as follows, in order of preference:
+    * try to find an exact match
+    * choose the biggest corresponding numerical type (biggest float, biggest complex, biggest int)
+
+Built-in Fused Types
+====================
+There are some built-in fused types available for convenience, these are::
+
+    cython.integral # int, long
+    cython.floating # float, double
+    cython.numeric  # long, double, double complex
+
+Casting Fused Functions
+=======================
+Fused ``cdef`` and ``cpdef`` functions may be cast or assigned to C function pointers as follows::
+
+    cdef myfunc(cython.floating, cython.integral):
+        ...
+
+    # assign directly
+    cdef object (*funcp)(float, int)
+    funcp = myfunc
+    funcp(f, i)
+
+    # alternatively, cast it
+    (<object (*)(float, int)> myfunc)(f, i)
+
+    # This is also valid
+    funcp = myfunc[float, int]
+    funcp(f, i)
+
+Type Checking Specializations
+=============================
+Decisions can be made based on the specializations of the fused parameters. False conditions are pruned
+to avoid invalid code. One may check with ``is``, ``is not`` and ``==`` and ``!=`` to see if a fused type
+is equal to a certain other non-fused type (to check the specialization), or use ``in`` and ``not in`` to
+figure out whether a specialization is part of another set of types (specified as a fused type). In
+example::
+
+    ctypedef fused bunch_of_types:
+        ...
+
+    ctypedef fused string_t:
+        cython.p_char
+        bytes
+        unicode
+
+    cdef cython.integral myfunc(cython.integral i, bunch_of_types s):
+        cdef int *int_pointer
+        cdef long *long_pointer
+
+        # Only one of these branches will be compiled for each specialization!
+        if cython.integral is int:
+            int_pointer = &i
+        else:
+            long_pointer = &i
+
+        if bunch_of_types in string_t:
+            print "s is a string!"
+
+__signatures__
+==============
+Finally, function objects from ``def`` or ``cpdef`` functions have an attribute __signatures__, which maps
+the signature strings to the actual specialized functions. This may be useful for inspection.
+Listed signature strings may also be used as indices to the fused function::
+
+    specialized_function = fused_function["MyExtensionClass, int, float"]
+
+It would usually be preferred to index like this, however::
+
+    specialized_function = fused_function[MyExtensionClass, int, float]
+
+Although the latter will select the biggest types for ``int`` and ``float`` from Python space, as they are
+not type identifiers but builtin types there. Passing ``cython.int`` and ``cython.float`` would resolve that,
+however.

docs/src/userguide/index.rst

@@ -15,6 +15,7 @@ Contents:
    external_C_code
    source_files_and_compilation
    wrapping_CPlusPlus
+   fusedtypes
    limitations
    pyrex_differences
    early_binding_for_speed

runtests.py

@@ -716,6 +716,7 @@ def run_forked_test(result, run_func, test_name, fork=True):
         gc.collect()
         return
 
+    module_name = test_name.split()[-1]
     # fork to make sure we do not keep the tested module loaded
     result_handle, result_file = tempfile.mkstemp()
     os.close(result_handle)

tests/errors/cpp_no_constructor.pyx

@@ -9,5 +9,5 @@ cdef extern from *:
 new Foo(1, 2)
 
 _ERRORS = u"""
-9:7: no suitable method found
+9:7: Call with wrong number of arguments (expected 1, got 2)
 """

tests/errors/e_fused_closure.pyx

+# mode: error
+
+cimport cython
+
+def closure(cython.integral i):
+    def inner(cython.floating f):
+        pass
+
+def closure2(cython.integral i):
+    return lambda cython.integral i: i
+
+def closure3(cython.integral i):
+    def inner():
+        return lambda cython.floating f: f
+
+def generator(cython.integral i):
+    yield i
+
+_ERRORS = u"""
+e_fused_closure.pyx:6:4: Cannot nest fused functions
+e_fused_closure.pyx:10:11: Cannot nest fused functions
+e_fused_closure.pyx:14:15: Cannot nest fused functions
+e_fused_closure.pyx:16:0: Fused generators not supported
+"""

tests/errors/e_public_cdef_private_types.pyx

+# mode: error
+
+ctypedef char *string_t
+ctypedef public char *public_string_t
+ctypedef api char *api_string_t
+
+# This should all fail
+cdef public pub_func1(string_t x):
+    pass
+
+cdef api api_func1(string_t x):
+    pass
+
+cdef public string_t pub_func2():
+    pass
+
+cdef api string_t api_func2():
+    pass
+
+cdef public opt_pub_func(x = None):
+    pass
+
+cdef api opt_api_func(x = None):
+    pass
+
+# This should all work
+cdef public pub_func3(public_string_t x, api_string_t y):
+    pass
+
+cdef api api_func3(public_string_t x, api_string_t y):
+    pass
+
+cdef opt_func(x = None):
+    pass
+
+_ERRORS = u"""
+e_public_cdef_private_types.pyx:8:22: Function declared public or api may not have private types
+e_public_cdef_private_types.pyx:11:19: Function declared public or api may not have private types
+e_public_cdef_private_types.pyx:14:5: Function declared public or api may not have private types
+e_public_cdef_private_types.pyx:17:5: Function declared public or api may not have private types
+e_public_cdef_private_types.pyx:20:25: Function with optional arguments may not be declared public or api
+e_public_cdef_private_types.pyx:23:22: Function with optional arguments may not be declared public or api
+"""

tests/errors/fused_syntax.pyx

+# mode: error
+
+cdef fused my_fused_type: int a; char b
+
+_ERRORS = u"""
+fused_syntax.pyx:3:26: Expected a newline
+"""

tests/errors/fused_syntax_ctypedef.pyx

+# mode: error
+
+cimport cython
+
+ctypedef cython.fused_type(int, float) fused_t
+
+_ERRORS = u"""
+fused_syntax_ctypedef.pyx:5:39: Syntax error in ctypedef statement
+"""

tests/errors/fused_types.pyx

+# mode: error
+
+cimport cython
+from cython import fused_type
+
+# This is all invalid
+# ctypedef foo(int) dtype1
+# ctypedef foo.bar(float) dtype2
+# ctypedef fused_type(foo) dtype3
+dtype4 = cython.fused_type(int, long, kw=None)
+
+# ctypedef public cython.fused_type(int, long) dtype7
+# ctypedef api cython.fused_type(int, long) dtype8
+
+int_t = cython.fused_type(short, short, int)
+int2_t = cython.fused_type(int, long)
+dtype9 = cython.fused_type(int2_t, int)
+
+floating = cython.fused_type(float, double)
+
+cdef func(floating x, int2_t y):
+    print x, y
+
+cdef float x = 10.0
+cdef int y = 10
+func[float](x, y)
+func[float][int](x, y)
+func[float, int](x)
+func[float, int](x, y, y)
+func(x, y=y)
+
+ctypedef fused memslice_dtype_t:
+    cython.p_int # invalid dtype
+    cython.long
+
+def f(memslice_dtype_t[:, :] a):
+    pass
+
+# This is all valid
+dtype5 = fused_type(int, long, float)
+dtype6 = cython.fused_type(int, long)
+func[float, int](x, y)
+
+cdef fused fused1:
+    int
+    long long
+
+ctypedef fused fused2:
+    int
+    long long
+
+func(x, y)
+
+_ERRORS = u"""
+fused_types.pyx:10:15: fused_type does not take keyword arguments
+fused_types.pyx:15:38: Type specified multiple times
+fused_types.pyx:17:33: Cannot fuse a fused type
+fused_types.pyx:26:4: Not enough types specified to specialize the function, int2_t is still fused
+fused_types.pyx:27:4: Not enough types specified to specialize the function, int2_t is still fused
+fused_types.pyx:28:16: Call with wrong number of arguments (expected 2, got 1)
+fused_types.pyx:29:16: Call with wrong number of arguments (expected 2, got 3)
+fused_types.pyx:30:4: Keyword and starred arguments not allowed in cdef functions.
+fused_types.pyx:36:6: Invalid base type for memoryview slice: int *
+"""

tests/errors/memview_declarations.pyx

@@ -59,10 +59,10 @@ _ERRORS = u'''
 20:22: Invalid axis specification.
 21:25: Invalid axis specification.
 22:22: no expressions allowed in axis spec, only names and literals.
-25:51: Memoryview 'object[::contiguous, :]' not conformable to memoryview 'object[:, ::contiguous]'.
+25:51: Memoryview 'object[::1, :]' not conformable to memoryview 'object[:, ::1]'.
 28:36: Different base types for memoryviews (int, Python object)
 31:9: Dimension may not be contiguous
 37:9: Only one direct contiguous axis may be specified.
 38:9:Only dimensions 3 and 2 may be contiguous and direct
-44:10: Invalid base type for memoryview slice
+44:10: Invalid base type for memoryview slice: intp
 '''

tests/run/check_fused_types.pyx

+cimport cython
+cimport check_fused_types_pxd
+
+import math
+
+ctypedef char *string_t
+
+fused_t = cython.fused_type(int, long, float, string_t)
+other_t = cython.fused_type(int, long)
+base_t = cython.fused_type(short, int)
+
+# complex_t = cython.fused_type(cython.floatcomplex, cython.doublecomplex)
+cdef fused complex_t:
+    float complex
+    double complex
+
+ctypedef base_t **base_t_p_p
+
+# ctypedef cython.fused_type(char, base_t_p_p, fused_t, complex_t) composed_t
+cdef fused composed_t:
+    char
+    int
+    float
+    string_t
+    cython.pp_int
+    float complex
+    double complex
+    int complex
+    long complex
+
+
+cdef func(fused_t a, other_t b):
+    cdef int int_a
+    cdef string_t string_a
+    cdef other_t other_a
+
+    if fused_t is other_t:
+        print 'fused_t is other_t'
+        other_a = a
+
+    if fused_t is int:
+        print 'fused_t is int'
+        int_a = a
+
+    if fused_t is string_t:
+        print 'fused_t is string_t'
+        string_a = a
+
+    if fused_t in check_fused_types_pxd.unresolved_t:
+        print 'fused_t in unresolved_t'
+
+    if int in check_fused_types_pxd.unresolved_t:
+        print 'int in unresolved_t'
+
+    if string_t in check_fused_types_pxd.unresolved_t:
+        print 'string_t in unresolved_t'
+
+
+def test_int_int():
+    """
+    >>> test_int_int()
+    fused_t is other_t
+    fused_t is int
+    fused_t in unresolved_t
+    int in unresolved_t
+    """
+    cdef int x = 1
+    cdef int y = 2
+
+    func(x, y)
+
+def test_int_long():
+    """
+    >>> test_int_long()
+    fused_t is int
+    fused_t in unresolved_t
+    int in unresolved_t
+    """
+    cdef int x = 1
+    cdef long y = 2
+
+    func(x, y)
+
+def test_float_int():
+    """
+    >>> test_float_int()
+    fused_t in unresolved_t
+    int in unresolved_t
+    """
+    cdef float x = 1
+    cdef int y = 2
+
+    func(x, y)
+
+def test_string_int():
+    """
+    >>> test_string_int()
+    fused_t is string_t
+    int in unresolved_t
+    """
+    cdef string_t x = b"spam"
+    cdef int y = 2
+
+    func(x, y)
+
+
+cdef if_then_else(fused_t a, other_t b):
+    cdef other_t other_a
+    cdef string_t string_a
+    cdef fused_t specific_a
+
+    if fused_t is other_t:
+        print 'fused_t is other_t'
+        other_a = a
+    elif fused_t is string_t:
+        print 'fused_t is string_t'
+        string_a = a
+    else:
+        print 'none of the above'
+        specific_a = a
+
+def test_if_then_else_long_long():
+    """
+    >>> test_if_then_else_long_long()
+    fused_t is other_t
+    """
+    cdef long x = 0, y = 0
+    if_then_else(x, y)
+
+def test_if_then_else_string_int():
+    """
+    >>> test_if_then_else_string_int()
+    fused_t is string_t
+    """
+    cdef string_t x = b"spam"
+    cdef int y = 0
+    if_then_else(x, y)
+
+def test_if_then_else_float_int():
+    """
+    >>> test_if_then_else_float_int()
+    none of the above
+    """
+    cdef float x = 0.0
+    cdef int y = 1
+    if_then_else(x, y)
+
+
+cdef composed_t composed(composed_t x, composed_t y):
+    if composed_t in base_t_p_p or composed_t is string_t:
+        if string_t == composed_t:
+            print x.decode('ascii'), y.decode('ascii')
+        else:
+            print x[0][0], y[0][0]
+
+        return x
+    elif composed_t == string_t:
+        print 'this is never executed'
+    elif list():
+        print 'neither is this one'
+    else:
+        if composed_t not in complex_t:
+            print 'not a complex number'
+            print <int> x, <int> y
+        else:
+            print 'it is a complex number'
+            print x.real, x.imag
+
+        return x + y
+
+def test_composed_types():
+    """
+    >>> test_composed_types()
+    it is a complex number
+    0.5 0.6
+    9 4
+    <BLANKLINE>
+    not a complex number
+    7 8
+    15
+    <BLANKLINE>
+    7 8
+    <BLANKLINE>
+    spam eggs
+    spam
+    """
+    cdef double complex a = 0.5 + 0.6j, b = 0.4 -0.2j, result
+    cdef int c = 7, d = 8
+    cdef int *cp = &c, *dp = &d
+    cdef string_t e = "spam", f = "eggs"
+
+    result = composed(a, b)
+    print int(math.ceil(result.real * 10)), int(math.ceil(result.imag * 10))
+    print
+
+    print composed(c, d)
+    print
+
+    composed(&cp, &dp)
+    print
+
+    print composed(e, f).decode('ascii')
+

tests/run/check_fused_types_pxd.pxd

+cimport cython
+
+unresolved_t = cython.fused_type(int, float)

tests/run/fused_cpdef.pyx

+cimport cython
+
+cy = __import__("cython")
+
+cpdef func1(self, cython.integral x):
+    print "%s," % (self,),
+    if cython.integral is int:
+        print 'x is int', x, cython.typeof(x)
+    else:
+        print 'x is long', x, cython.typeof(x)
+
+
+class A(object):
+    meth = func1
+
+    def __str__(self):
+        return "A"
+
+pyfunc = func1
+
+def test_fused_cpdef():
+    """
+    >>> test_fused_cpdef()
+    None, x is int 2 int
+    None, x is long 2 long
+    None, x is long 2 long
+    <BLANKLINE>
+    None, x is int 2 int
+    None, x is long 2 long
+    <BLANKLINE>
+    A, x is int 2 int
+    A, x is long 2 long
+    A, x is long 2 long
+    A, x is long 2 long
+    """
+    func1[int](None, 2)
+    func1[long](None, 2)
+    func1(None, 2)
+
+    print
+
+    pyfunc[cy.int](None, 2)
+    pyfunc(None, 2)
+
+    print
+
+    A.meth[cy.int](A(), 2)
+    A.meth(A(), 2)
+    A().meth[cy.long](2)
+    A().meth(2)
+
+
+def assert_raise(func, *args):
+    try:
+        func(*args)
+    except TypeError:
+        pass
+    else:
+        assert False, "Function call did not raise TypeError"
+
+def test_badcall():
+    """
+    >>> test_badcall()
+    """
+    assert_raise(pyfunc)
+    assert_raise(pyfunc, 1, 2, 3)
+    assert_raise(pyfunc[cy.int], 10, 11, 12)
+    assert_raise(pyfunc, None, object())
+    assert_raise(A().meth)
+    assert_raise(A.meth)
+    assert_raise(A().meth[cy.int])
+    assert_raise(A.meth[cy.int])
+
+ctypedef long double long_double
+
+cpdef multiarg(cython.integral x, cython.floating y):
+    if cython.integral is int:
+        print "x is an int,",
+    else:
+        print "x is a long,",
+
+    if cython.floating is long_double:
+        print "y is a long double:",
+    elif float is cython.floating:
+        print "y is a float:",
+    else:
+        print "y is a double:",
+
+    print x, y
+
+def test_multiarg():
+    """
+    >>> test_multiarg()
+    x is an int, y is a float: 1 2.0
+    x is an int, y is a float: 1 2.0
+    x is a long, y is a double: 4 5.0
+    """
+    multiarg[int, float](1, 2.0)
+    multiarg[cy.int, cy.float](1, 2.0)
+    multiarg(4, 5.0)

tests/run/fused_def.pyx

+# mode: run
+
+"""
+Test Python def functions without extern types
+"""
+
+cy = __import__("cython")
+cimport cython
+
+cdef class Base(object):
+    def __repr__(self):
+        return type(self).__name__
+
+
+cdef class ExtClassA(Base):
+    pass
+
+cdef class ExtClassB(Base):
+    pass
+
+cdef enum MyEnum:
+    entry0
+    entry1
+    entry2
+    entry3
+    entry4
+
+ctypedef fused fused_t:
+    str
+    int
+    long
+    complex
+    ExtClassA
+    ExtClassB
+    MyEnum
+
+
+f = 5.6
+i = 9
+
+def opt_func(fused_t obj, cython.floating myf = 1.2, cython.integral myi = 7):
+    """
+    Test runtime dispatch, indexing of various kinds and optional arguments
+
+    >>> opt_func("spam", f, i)
+    str object double long
+    spam 5.60 9 5.60 9
+    >>> opt_func[str, float, int]("spam", f, i)
+    str object float int
+    spam 5.60 9 5.60 9
+    >>> opt_func["str, double, long"]("spam", f, i)
+    str object double long
+    spam 5.60 9 5.60 9
+    >>> opt_func[str, float, cy.int]("spam", f, i)
+    str object float int
+    spam 5.60 9 5.60 9
+
+
+    >>> opt_func(ExtClassA(), f, i)
+    ExtClassA double long
+    ExtClassA 5.60 9 5.60 9
+    >>> opt_func[ExtClassA, float, int](ExtClassA(), f, i)
+    ExtClassA float int
+    ExtClassA 5.60 9 5.60 9
+    >>> opt_func["ExtClassA, double, long"](ExtClassA(), f, i)
+    ExtClassA double long
+    ExtClassA 5.60 9 5.60 9
+
+    >>> opt_func(ExtClassB(), f, i)
+    ExtClassB double long
+    ExtClassB 5.60 9 5.60 9
+    >>> opt_func[ExtClassB, cy.double, cy.long](ExtClassB(), f, i)
+    ExtClassB double long
+    ExtClassB 5.60 9 5.60 9
+
+    >>> opt_func(10, f)
+    long double long
+    10 5.60 7 5.60 9
+    >>> opt_func[int, float, int](10, f)
+    int float int
+    10 5.60 7 5.60 9
+
+    >>> opt_func(10 + 2j, myf = 2.6)
+    double complex double long
+    (10+2j) 2.60 7 5.60 9
+    >>> opt_func[cy.py_complex, float, int](10 + 2j, myf = 2.6)
+    double complex float int
+    (10+2j) 2.60 7 5.60 9
+    >>> opt_func[cy.doublecomplex, cy.float, cy.int](10 + 2j, myf = 2.6)
+    double complex float int
+    (10+2j) 2.60 7 5.60 9
+
+    >>> opt_func(object(), f)
+    Traceback (most recent call last):
+      ...
+    TypeError: Function call with ambiguous argument types
+    >>> opt_func[ExtClassA, cy.float, cy.long](object(), f)
+    Traceback (most recent call last):
+      ...
+    TypeError: Argument 'obj' has incorrect type (expected fused_def.ExtClassA, got object)
+    """
+    print cython.typeof(obj), cython.typeof(myf), cython.typeof(myi)
+    print obj, "%.2f" % myf, myi, "%.2f" % f, i
+
+
+def test_opt_func():
+    """
+    >>> test_opt_func()
+    str object double long
+    ham 5.60 4 5.60 9
+    """
+    opt_func("ham", f, entry4)
+
+def args_kwargs(fused_t obj, cython.floating myf = 1.2, *args, **kwargs):
+    """
+    >>> args_kwargs("foo")
+    str object double
+    foo 1.20 5.60 () {}
+
+    >>> args_kwargs("eggs", f, 1, 2, [], d={})
+    str object double
+    eggs 5.60 5.60 (1, 2, []) {'d': {}}
+
+    >>> args_kwargs[str, float]("eggs", f, 1, 2, [], d={})
+    str object float
+    eggs 5.60 5.60 (1, 2, []) {'d': {}}
+
+    """
+    print cython.typeof(obj), cython.typeof(myf)
+    print obj, "%.2f" % myf, "%.2f" % f, args, kwargs

tests/run/fused_types.pyx

+# mode: run
+
+cimport cython
+from cython cimport integral
+from cpython cimport Py_INCREF
+
+from Cython import Shadow as pure_cython
+
+ctypedef char * string_t
+
+# floating = cython.fused_type(float, double) floating
+# integral = cython.fused_type(int, long) integral
+ctypedef cython.floating floating
+fused_type1 = cython.fused_type(int, long, float, double, string_t)
+fused_type2 = cython.fused_type(string_t)
+ctypedef fused_type1 *composed_t
+other_t = cython.fused_type(int, double)
+ctypedef double *p_double
+ctypedef int *p_int
+
+
+def test_pure():
+    """
+    >>> test_pure()
+    10
+    """
+    mytype = pure_cython.typedef(pure_cython.fused_type(int, long, complex))
+    print mytype(10)
+
+
+cdef cdef_func_with_fused_args(fused_type1 x, fused_type1 y, fused_type2 z):
+    if fused_type1 is string_t:
+        print x.decode('ascii'), y.decode('ascii'), z.decode('ascii')
+    else:
+        print x, y, z.decode('ascii')
+
+    return x + y
+
+def test_cdef_func_with_fused_args():
+    """
+    >>> test_cdef_func_with_fused_args()
+    spam ham eggs
+    spamham
+    10 20 butter
+    30
+    4.2 8.6 bunny
+    12.8
+    """
+    print cdef_func_with_fused_args('spam', 'ham', 'eggs').decode('ascii')
+    print cdef_func_with_fused_args(10, 20, 'butter')
+    print cdef_func_with_fused_args(4.2, 8.6, 'bunny')
+
+cdef fused_type1 fused_with_pointer(fused_type1 *array):
+    for i in range(5):
+        if fused_type1 is string_t:
+            print array[i].decode('ascii')
+        else:
+            print array[i]
+
+    obj = array[0] + array[1] + array[2] + array[3] + array[4]
+    # if cython.typeof(fused_type1) is string_t:
+    Py_INCREF(obj)
+    return obj
+
+def test_fused_with_pointer():
+    """
+    >>> test_fused_with_pointer()
+    0
+    1
+    2
+    3
+    4
+    10
+    <BLANKLINE>
+    0
+    1
+    2
+    3
+    4
+    10
+    <BLANKLINE>
+    0.0
+    1.0
+    2.0
+    3.0
+    4.0
+    10.0
+    <BLANKLINE>
+    humpty
+    dumpty
+    fall
+    splatch
+    breakfast
+    humptydumptyfallsplatchbreakfast
+    """
+    cdef int int_array[5]
+    cdef long long_array[5]
+    cdef float float_array[5]
+    cdef string_t string_array[5]
+
+    cdef char *s
+
+    strings = [b"humpty", b"dumpty", b"fall", b"splatch", b"breakfast"]
+
+    for i in range(5):
+        int_array[i] = i
+        long_array[i] = i
+        float_array[i] = i
+        s = strings[i]
+        string_array[i] = s
+
+    print fused_with_pointer(int_array)
+    print
+    print fused_with_pointer(long_array)
+    print
+    print fused_with_pointer(float_array)
+    print
+    print fused_with_pointer(string_array).decode('ascii')
+
+include "cythonarrayutil.pxi"
+
+cpdef cython.integral test_fused_memoryviews(cython.integral[:, ::1] a):
+    """
+    >>> import cython
+    >>> a = create_array((3, 5), mode="c")
+    >>> test_fused_memoryviews[cython.int](a)
+    7
+    """
+    return a[1, 2]
+
+ctypedef int[:, ::1] memview_int
+ctypedef long[:, ::1] memview_long
+memview_t = cython.fused_type(memview_int, memview_long)
+
+def test_fused_memoryview_def(memview_t a):
+    """
+    >>> a = create_array((3, 5), mode="c")
+    >>> test_fused_memoryview_def["memview_int"](a)
+    7
+    """
+    return a[1, 2]
+
+cdef test_specialize(fused_type1 x, fused_type1 *y, composed_t z, other_t *a):
+    cdef fused_type1 result
+
+    if composed_t is p_double:
+        print "double pointer"
+
+    if fused_type1 in floating:
+        result = x + y[0] + z[0] + a[0]
+        return result
+
+def test_specializations():
+    """
+    >>> test_specializations()
+    double pointer
+    double pointer
+    double pointer
+    double pointer
+    double pointer
+    """
+    cdef object (*f)(double, double *, double *, int *)
+
+    cdef double somedouble = 2.2
+    cdef double otherdouble = 3.3
+    cdef int someint = 4
+
+    cdef p_double somedouble_p = &somedouble
+    cdef p_double otherdouble_p = &otherdouble
+    cdef p_int someint_p = &someint
+
+    f = test_specialize
+    assert f(1.1, somedouble_p, otherdouble_p, someint_p) == 10.6
+
+    f = <object (*)(double, double *, double *, int *)> test_specialize
+    assert f(1.1, somedouble_p, otherdouble_p, someint_p) == 10.6
+
+    assert (<object (*)(double, double *, double *, int *)>
+            test_specialize)(1.1, somedouble_p, otherdouble_p, someint_p) == 10.6
+
+    f = test_specialize[double, int]
+    assert f(1.1, somedouble_p, otherdouble_p, someint_p) == 10.6
+
+    assert test_specialize[double, int](1.1, somedouble_p, otherdouble_p, someint_p) == 10.6
+
+    # The following cases are not supported
+    # f = test_specialize[double][p_int]
+    # print f(1.1, somedouble_p, otherdouble_p)
+    # print
+
+    # print test_specialize[double][p_int](1.1, somedouble_p, otherdouble_p)
+    # print
+
+    # print test_specialize[double](1.1, somedouble_p, otherdouble_p)
+    # print
+
+cdef opt_args(integral x, floating y = 4.0):
+    print x, y
+
+def test_opt_args():
+    """
+    >>> test_opt_args()
+    3 4.0
+    3 4.0
+    3 4.0
+    3 4.0
+    """
+    opt_args[int,  float](3)
+    opt_args[int, double](3)
+    opt_args[int,  float](3, 4.0)
+    opt_args[int, double](3, 4.0)
+