keyword argument support, removed last traces of std::function<> usage

include/pybind/numpy.h

@@ -10,6 +10,8 @@
 #pragma once
 
 #include <pybind/pybind.h>
+#include <functional>
+
 #if defined(_MSC_VER)
 #pragma warning(push)
 #pragma warning(disable: 4127) // warning C4127: Conditional expression is constant
@@ -132,6 +134,15 @@ public:
     }
 };
 
+#define DECL_FMT(t, n) template<> struct npy_format_descriptor<t> { enum { value = array::API::n }; }
+DECL_FMT(int8_t, NPY_BYTE);  DECL_FMT(uint8_t, NPY_UBYTE); DECL_FMT(int16_t, NPY_SHORT);
+DECL_FMT(uint16_t, NPY_USHORT); DECL_FMT(int32_t, NPY_INT); DECL_FMT(uint32_t, NPY_UINT);
+DECL_FMT(int64_t, NPY_LONGLONG); DECL_FMT(uint64_t, NPY_ULONGLONG); DECL_FMT(float, NPY_FLOAT);
+DECL_FMT(double, NPY_DOUBLE); DECL_FMT(bool, NPY_BOOL); DECL_FMT(std::complex<float>, NPY_CFLOAT);
+DECL_FMT(std::complex<double>, NPY_CDOUBLE);
+#undef DECL_FMT
+
+
 NAMESPACE_BEGIN(detail)
 PYBIND_TYPE_CASTER_PYTYPE(array)
 PYBIND_TYPE_CASTER_PYTYPE(array_dtype<int8_t>)  PYBIND_TYPE_CASTER_PYTYPE(array_dtype<uint8_t>)
@@ -142,24 +153,20 @@ PYBIND_TYPE_CASTER_PYTYPE(array_dtype<float>)   PYBIND_TYPE_CASTER_PYTYPE(array_
 PYBIND_TYPE_CASTER_PYTYPE(array_dtype<std::complex<float>>)
 PYBIND_TYPE_CASTER_PYTYPE(array_dtype<std::complex<double>>)
 PYBIND_TYPE_CASTER_PYTYPE(array_dtype<bool>)
-NAMESPACE_END(detail)
 
-#define DECL_FMT(t, n) template<> struct npy_format_descriptor<t> { enum { value = array::API::n }; }
-DECL_FMT(int8_t, NPY_BYTE);  DECL_FMT(uint8_t, NPY_UBYTE); DECL_FMT(int16_t, NPY_SHORT);
-DECL_FMT(uint16_t, NPY_USHORT); DECL_FMT(int32_t, NPY_INT); DECL_FMT(uint32_t, NPY_UINT);
-DECL_FMT(int64_t, NPY_LONGLONG); DECL_FMT(uint64_t, NPY_ULONGLONG); DECL_FMT(float, NPY_FLOAT);
-DECL_FMT(double, NPY_DOUBLE); DECL_FMT(bool, NPY_BOOL); DECL_FMT(std::complex<float>, NPY_CFLOAT);
-DECL_FMT(std::complex<double>, NPY_CDOUBLE);
-#undef DECL_FMT
+template <typename Func, typename Return, typename... Args>
+struct vectorize_helper {
+    typename std::remove_reference<Func>::type f;
+
+    vectorize_helper(const Func &f) : f(f) { }
 
-template <typename func_type, typename return_type, typename... args_type, size_t... Index>
-    std::function<object(array_dtype<args_type>...)>
-        vectorize(func_type &&f, return_type (*) (args_type ...),
-                  detail::index_sequence<Index...>) {
+    object operator()(array_dtype<Args>... args) {
+        return run(args..., typename make_index_sequence<sizeof...(Args)>::type());
+    }
 
-    return [f](array_dtype<args_type>... args) -> array {
+    template <size_t ... Index> object run(array_dtype<Args>&... args, index_sequence<Index...>) {
         /* Request buffers from all parameters */
-        const size_t N = sizeof...(args_type);
+        const size_t N = sizeof...(Args);
         std::array<buffer_info, N> buffers {{ args.request()... }};
 
         /* Determine dimensions parameters of output array */
@@ -174,7 +181,7 @@ template <typename func_type, typename return_type, typename... args_type, size_
         }
         std::vector<size_t> strides(ndim);
         if (ndim > 0) {
-            strides[ndim-1] = sizeof(return_type);
+            strides[ndim-1] = sizeof(Return);
             for (int i=ndim-1; i>0; --i)
                 strides[i-1] = strides[i] * shape[i];
         }
@@ -186,31 +193,32 @@ template <typename func_type, typename return_type, typename... args_type, size_
         }
 
         /* Call the function */
-        std::vector<return_type> result(count);
+        std::vector<Return> result(count);
         for (size_t i=0; i<count; ++i)
             result[i] = f((buffers[Index].count == 1
-                               ? *((args_type *) buffers[Index].ptr)
-                               :  ((args_type *) buffers[Index].ptr)[i])...);
+                               ? *((Args *) buffers[Index].ptr)
+                               :  ((Args *) buffers[Index].ptr)[i])...);
 
         if (count == 1)
             return cast(result[0]);
 
         /* Return the result */
-        return array(buffer_info(result.data(), sizeof(return_type),
-            format_descriptor<return_type>::value(),
+        return array(buffer_info(result.data(), sizeof(Return),
+            format_descriptor<Return>::value(),
             ndim, shape, strides));
-    };
-}
+    }
+};
+
+NAMESPACE_END(detail)
 
-template <typename func_type, typename return_type, typename... args_type>
-    std::function<object(array_dtype<args_type>...)>
-        vectorize(func_type &&f, return_type (*f_) (args_type ...) = nullptr) {
-    return vectorize(f, f_, typename detail::make_index_sequence<sizeof...(args_type)>::type());
+template <typename Func, typename Return, typename... Args>
+detail::vectorize_helper<Func, Return, Args...> vectorize(const Func &f, Return (*) (Args ...)) {
+    return detail::vectorize_helper<Func, Return, Args...>(f);
 }
 
-template <typename return_type, typename... args_type>
-std::function<object(array_dtype<args_type>...)> vectorize(return_type (*f) (args_type ...)) {
-    return vectorize(f, f);
+template <typename Return, typename... Args>
+detail::vectorize_helper<Return (*) (Args ...), Return, Args...> vectorize(Return (*f) (Args ...)) {
+    return vectorize<Return (*) (Args ...), Return, Args...>(f, f);
 }
 
 template <typename func> auto vectorize(func &&f) -> decltype(

include/pybind/pybind.h

@@ -76,26 +76,82 @@ private:
     template <typename... T> using arg_value_caster =
         detail::type_caster<typename std::tuple<T...>>;
 
-
-    template <typename... T> void process_args(const std::tuple<T...> &args, function_entry *entry) {
-        process_args(args, entry, typename detail::make_index_sequence<sizeof...(T)>::type());
+    template <typename... T> static void process_extras(const std::tuple<T...> &args,
+            function_entry *entry, const char **kw, const char **def) {
+        process_extras(args, entry, kw, def, typename detail::make_index_sequence<sizeof...(T)>::type());
     }
 
-    template <typename... T, size_t ... Index> void process_args(const
-            std::tuple<T...> &args, function_entry *entry,
-            detail::index_sequence<Index...>) {
-        int unused[] = { 0, (process_arg(std::get<Index>(args), entry), 0)... };
+    template <typename... T, size_t ... Index> static void process_extras(const std::tuple<T...> &args,
+            function_entry *entry, const char **kw, const char **def, detail::index_sequence<Index...>) {
+        int unused[] = { 0, (process_extra(std::get<Index>(args), entry, kw, def), 0)... };
         (void) unused;
     }
 
-    void process_arg(const char *doc, function_entry *entry) { entry->doc = doc; }
-    void process_arg(const pybind::doc &d, function_entry *entry) { entry->doc = d.value; }
-    void process_arg(const pybind::name &n, function_entry *entry) { entry->name = n.value; }
-    void process_arg(const pybind::arg &, function_entry *entry) { entry->keywords++; }
-    void process_arg(const pybind::is_method &, function_entry *entry) { entry->is_method = true; }
-    void process_arg(const pybind::return_value_policy p, function_entry *entry) { entry->policy = p; }
-    void process_arg(pybind::sibling s, function_entry *entry) { entry->sibling = s.value; }
+    template <typename... T> static void process_extras(const std::tuple<T...> &args,
+            PyObject *pyArgs, PyObject *kwargs, bool is_method) {
+        process_extras(args, pyArgs, kwargs, is_method, typename detail::make_index_sequence<sizeof...(T)>::type());
+    }
 
+    template <typename... T, size_t... Index> static void process_extras(const std::tuple<T...> &args,
+            PyObject *pyArgs, PyObject *kwargs, bool is_method, detail::index_sequence<Index...>) {
+        int index = is_method ? 1 : 0;
+        int unused[] = { 0, (process_extra(std::get<Index>(args), index, pyArgs, kwargs), 0)... };
+        (void) unused;
+    }
+
+    static void process_extra(const char *doc, function_entry *entry, const char **, const char **) { entry->doc = doc; }
+    static void process_extra(const pybind::doc &d, function_entry *entry, const char **, const char **) { entry->doc = d.value; }
+    static void process_extra(const pybind::name &n, function_entry *entry, const char **, const char **) { entry->name = n.value; }
+    static void process_extra(const pybind::arg &a, function_entry *entry, const char **kw, const char **) {
+        if (entry->is_method && entry->keywords == 0)
+            kw[entry->keywords++] = "self";
+        kw[entry->keywords++] = a.name;
+    }
+    template <typename T>
+    static void process_extra(const pybind::arg_t<T> &a, function_entry *entry, const char **kw, const char **def) {
+        if (entry->is_method && entry->keywords == 0)
+            kw[entry->keywords++] = "self";
+        kw[entry->keywords] = a.name;
+        def[entry->keywords++] = strdup(std::to_string(a.value).c_str());
+    }
+
+    static void process_extra(const pybind::is_method &, function_entry *entry, const char **, const char **) { entry->is_method = true; }
+    static void process_extra(const pybind::return_value_policy p, function_entry *entry, const char **, const char **) { entry->policy = p; }
+    static void process_extra(pybind::sibling s, function_entry *entry, const char **, const char **) { entry->sibling = s.value; }
+
+    template <typename T> static void process_extra(T, int &, PyObject *, PyObject *) { }
+    static void process_extra(const pybind::arg &a, int &index, PyObject *args, PyObject *kwargs) {
+        if (kwargs) {
+            if (PyTuple_GET_ITEM(args, index) != nullptr) {
+                index++;
+                return;
+            }
+            PyObject *value = PyDict_GetItemString(kwargs, a.name);
+            if (value) {
+                Py_INCREF(value);
+                PyTuple_SetItem(args, index, value);
+            }
+        }
+        index++;
+    }
+    template <typename T>
+    static void process_extra(const pybind::arg_t<T> &a, int &index, PyObject *args, PyObject *kwargs) {
+        if (PyTuple_GET_ITEM(args, index) != nullptr) {
+            index++;
+            return;
+        }
+        PyObject *value = nullptr;
+        if (kwargs)
+            value = PyDict_GetItemString(kwargs, a.name);
+        if (value) {
+            Py_INCREF(value);
+        } else {
+            value = detail::type_caster<typename detail::decay<T>::type>::cast(
+                a.value, return_value_policy::automatic, nullptr);
+        }
+        PyTuple_SetItem(args, index, value);
+        index++;
+    }
 public:
     cpp_function() { }
 
@@ -104,7 +160,7 @@ public:
     cpp_function(Return (*f)(Arg...), Extra&&... extra) {
         struct capture {
             Return (*f)(Arg...);
-            std::tuple<Extra...> extra;
+            std::tuple<Extra...> extras;
         };
 
         function_entry *entry = new function_entry();
@@ -114,18 +170,23 @@ public:
         typedef return_value_caster<Return> cast_out;
 
         entry->impl = [](function_entry *entry, PyObject *pyArgs, PyObject *kwargs, PyObject *parent) -> PyObject * {
+            capture *data = (capture *) entry->data;
+            process_extras(data->extras, pyArgs, kwargs, entry->is_method);
             cast_in args;
-            if (!args.load(pyArgs, true)) return nullptr;
-            auto f = ((capture *) entry->data)->f;
-            (void)kwargs;
-            return cast_out::cast(args.template call<Return>(f), entry->policy, parent);
+            if (!args.load(pyArgs, true))
+                return nullptr;
+            return cast_out::cast(args.template call<Return>(data->f), entry->policy, parent);
         };
 
-        entry->signature = cast_in::name();
+        const int N = sizeof...(Extra) > sizeof...(Arg) ? sizeof...(Extra) : sizeof...(Arg);
+        std::array<const char *, N> kw{}, def{};
+        process_extras(((capture *) entry->data)->extras, entry, kw.data(), def.data());
+
+        entry->signature = cast_in::name(kw.data(), def.data());
         entry->signature += " -> ";
         entry->signature += cast_out::name();
-        process_args(((capture *) entry->data)->extra, entry);
-        initialize(entry);
+
+        initialize(entry, sizeof...(Arg));
     }
 
     /// Delegating helper constructor to deal with lambda functions
@@ -136,7 +197,6 @@ public:
                    std::forward<Extra>(extra)...);
     }
 
-
     /// Class methods (non-const)
     template <typename Return, typename Class, typename... Arg, typename... Extra> cpp_function(
             Return (Class::*f)(Arg...), Extra&&... extra) {
@@ -157,7 +217,7 @@ private:
     void initialize(Func &&f, Return (*)(Arg...), Extra&&... extra) {
         struct capture {
             typename std::remove_reference<Func>::type f;
-            std::tuple<Extra...> extra;
+            std::tuple<Extra...> extras;
         };
 
         function_entry *entry = new function_entry();
@@ -167,27 +227,50 @@ private:
         typedef return_value_caster<Return> cast_out;
 
         entry->impl = [](function_entry *entry, PyObject *pyArgs, PyObject *kwargs, PyObject *parent) -> PyObject *{
+            capture *data = (capture *)entry->data;
+            process_extras(data->extras, pyArgs, kwargs, entry->is_method);
             cast_in args;
-            if (!args.load(pyArgs, true)) return nullptr;
-            Func &f = ((capture *) entry->data)->f;
-            (void)kwargs;
-            return cast_out::cast(args.template call<Return>(f), entry->policy, parent);
+            if (!args.load(pyArgs, true))
+                return nullptr;
+            return cast_out::cast(args.template call<Return>(data->f), entry->policy, parent);
         };
 
-        entry->signature = cast_in::name();
+        const int N = sizeof...(Extra) > sizeof...(Arg) ? sizeof...(Extra) : sizeof...(Arg);
+        std::array<const char *, N> kw{}, def{};
+        process_extras(((capture *) entry->data)->extras, entry, kw.data(), def.data());
+
+        entry->signature = cast_in::name(kw.data(), def.data());
         entry->signature += " -> ";
         entry->signature += cast_out::name();
-        process_args(((capture *) entry->data)->extra, entry);
-        initialize(entry);
+
+        initialize(entry, sizeof...(Arg));
     }
 
     static PyObject *dispatcher(PyObject *self, PyObject *args, PyObject *kwargs ) {
         function_entry *overloads = (function_entry *) PyCapsule_GetPointer(self, nullptr);
+        int nargs = (int) PyTuple_Size(args);
         PyObject *result = nullptr;
-        PyObject *parent = PyTuple_Size(args) > 0 ? PyTuple_GetItem(args, 0) : nullptr;
+        PyObject *parent = nargs > 0 ? PyTuple_GetItem(args, 0) : nullptr;
         try {
             for (function_entry *it = overloads; it != nullptr; it = it->next) {
-                if ((result = it->impl(it, args, kwargs, parent)) != nullptr)
+                PyObject *args_ = args;
+
+                if (it->keywords != 0 && it->keywords != nargs) {
+                    args_ = PyTuple_New(it->keywords);
+                    for (int i=0; i<nargs; ++i) {
+                        PyObject *item = PyTuple_GET_ITEM(args, i);
+                        Py_INCREF(item);
+                        PyTuple_SET_ITEM(args_, i, item);
+                    }
+                }
+
+                result = it->impl(it, args_, kwargs, parent);
+
+                if (args_ != args) {
+                    Py_DECREF(args_);
+                }
+
+                if (result != nullptr)
                     break;
             }
         } catch (const error_already_set &) {                                               return nullptr;
@@ -221,9 +304,14 @@ private:
         }
     }
 
-    void initialize(function_entry *entry) {
+    void initialize(function_entry *entry, int args) {
         if (entry->name == nullptr)
             entry->name = "";
+        if (entry->keywords != 0 && entry->keywords != args)
+            throw std::runtime_error(
+                "cpp_function(): function \"" + std::string(entry->name) + "\" takes " +
+                std::to_string(args) + " arguments, but " + std::to_string(entry->keywords) +
+                " pybind::arg entries were specified!");
 
         entry->is_constructor = !strcmp(entry->name, "__init__");
 
@@ -578,32 +666,32 @@ public:
         return *this;
     }
 
-    class_ &def_property_readonly(const char *name, const cpp_function &fget) {
-        def_property(name, fget, cpp_function());
+    class_ &def_property_readonly(const char *name, const cpp_function &fget, const char *doc = nullptr) {
+        def_property(name, fget, cpp_function(), doc);
         return *this;
     }
 
-    class_ &def_property_readonly_static(const char *name, const cpp_function &fget) {
-        def_property_static(name, fget, cpp_function());
+    class_ &def_property_readonly_static(const char *name, const cpp_function &fget, const char *doc = nullptr) {
+        def_property_static(name, fget, cpp_function(), doc);
         return *this;
     }
 
-    class_ &def_property(const char *name, const cpp_function &fget, const cpp_function &fset) {
+    class_ &def_property(const char *name, const cpp_function &fget, const cpp_function &fset, const char *doc = nullptr) {
+        object doc_obj = doc ? pybind::str(doc) : (object) const_cast<cpp_function&>(fget).attr("__doc__");
         object property(
             PyObject_CallFunction((PyObject *)&PyProperty_Type,
                                   const_cast<char *>("OOOO"), fget.ptr() ? fget.ptr() : Py_None,
-                                  fset.ptr() ? fset.ptr() : Py_None, Py_None,
-                                  ((object) const_cast<cpp_function&>(fget).attr("__doc__")).ptr()), false);
+                                  fset.ptr() ? fset.ptr() : Py_None, Py_None, doc_obj.ptr()), false);
         attr(name) = property;
         return *this;
     }
 
-    class_ &def_property_static(const char *name, const cpp_function &fget, const cpp_function &fset) {
+    class_ &def_property_static(const char *name, const cpp_function &fget, const cpp_function &fset, const char *doc = nullptr) {
+        object doc_obj = doc ? pybind::str(doc) : (object) const_cast<cpp_function&>(fget).attr("__doc__");
         object property(
             PyObject_CallFunction((PyObject *)&PyProperty_Type,
-                                  const_cast<char *>("OOOO"), fget.ptr() ? fget.ptr() : Py_None,
-                                  fset.ptr() ? fset.ptr() : Py_None, Py_None,
-                                  ((object) const_cast<cpp_function&>(fget).attr("__doc__")).ptr()), false);
+                                  const_cast<char *>("OOOs"), fget.ptr() ? fget.ptr() : Py_None,
+                                  fset.ptr() ? fset.ptr() : Py_None, Py_None, doc_obj.ptr()), false);
         metaclass().attr(name) = property;
         return *this;
     }