Use exception values in C++ conversion, consolidate boilerplate.

Cython/Compiler/PyrexTypes.py

@@ -3019,18 +3019,34 @@ class CppClassType(CType):
         if self.from_py_function is not None:
             return True
         if self.cname in builtin_cpp_conversions:
+            X = "XYZABC"
             tags = []
-            context = {}
+            declarations = ["cdef extern from *:"]
             for ix, T in enumerate(self.templates or []):
                 if T.is_pyobject or not T.create_from_py_utility_code(env):
                     return False
                 tags.append(T.specialization_name())
-                # TODO: exception values
-                context["T%s" % ix] = T.declaration_code("")
-                context["T%s_from_py" % ix] = T.from_py_function
+                if T.exception_value is not None:
+                    except_clause = T.exception_value
+                    if T.exception_check:
+                        except_clause = "? %s" % except_clause
+                    declarations.append(
+                        "    ctypedef %s %s '%s'" % (
+                             T.declaration_code("", for_display=True), X[ix], T.declaration_code("")))
+                else:
+                    except_clause = "*"
+                    declarations.append(
+                        "    ctypedef struct %s '%s':\n        pass" % (
+                             X[ix], T.declaration_code("")))
+                declarations.append(
+                    "    cdef %s %s_from_py '%s' (object) except %s" % (
+                         X[ix], X[ix], T.from_py_function, except_clause))
             cls = self.cname[5:]
-            cname = "__pyx_convert_%s_from_py_%s" % (cls, "____".join(tags))
-            context['cname'] = cname
+            cname = '__pyx_convert_%s_from_py_%s' % (cls, '____'.join(tags))
+            context = {
+                'template_type_declarations': '\n'.join(declarations),
+                'cname': cname
+            }
             from UtilityCode import CythonUtilityCode
             env.use_utility_code(CythonUtilityCode.load(cls + ".from_py", "CppConvert.pyx", context=context))
             self.from_py_function = cname
@@ -3040,17 +3056,25 @@ class CppClassType(CType):
         if self.to_py_function is not None:
             return True
         if self.cname in builtin_cpp_conversions:
+            X = "XYZABC"
             tags = []
-            context = {}
+            declarations = ["cdef extern from *:"]
             for ix, T in enumerate(self.templates or []):
                 if not T.create_to_py_utility_code(env):
                     return False
                 tags.append(T.specialization_name())
-                context["T%s" % ix] = T.declaration_code("")
-                context["T%s_to_py" % ix] = T.to_py_function
+                declarations.append(
+                    "    ctypedef struct %s '%s':\n        pass" % (
+                         X[ix], T.declaration_code("")))
+                declarations.append(
+                    "    cdef object %s_to_py '%s' (%s)" % (
+                         X[ix], T.to_py_function, X[ix]))
             cls = self.cname[5:]
             cname = "__pyx_convert_%s_to_py_%s" % (cls, "____".join(tags))
-            context['cname'] = cname
+            context = {
+                'template_type_declarations': '\n'.join(declarations),
+                'cname': cname
+            }
             from UtilityCode import CythonUtilityCode
             env.use_utility_code(CythonUtilityCode.load(cls + ".to_py", "CppConvert.pyx", context=context))
             self.to_py_function = cname

Cython/Utility/CppConvert.pyx

@@ -28,10 +28,7 @@ cdef object {{cname}}(string& s):
 
 #################### vector.from_py ####################
 
-cdef extern from *:
-    ctypedef struct X "{{T0}}":
-        pass
-    cdef X X_from_py "{{T0_from_py}}" (object) except *
+{{template_type_declarations}}
 
 cdef extern from *:
     cdef cppclass vector "std::vector" [T]:
@@ -47,10 +44,7 @@ cdef vector[X] {{cname}}(object o) except *:
 
 #################### vector.to_py ####################
 
-cdef extern from *:
-    ctypedef struct X "{{T0}}":
-        pass
-    cdef object X_to_py "{{T0_to_py}}" (X)
+{{template_type_declarations}}
 
 cdef extern from *:
     cdef cppclass vector "const std::vector" [T]:
@@ -64,10 +58,7 @@ cdef object {{cname}}(vector[X]& v):
 
 #################### list.from_py ####################
 
-cdef extern from *:
-    ctypedef struct X "{{T0}}":
-        pass
-    cdef X X_from_py "{{T0_from_py}}" (object) except *
+{{template_type_declarations}}
 
 cdef extern from *:
     cdef cppclass cpp_list "std::list" [T]:
@@ -85,10 +76,7 @@ cdef cpp_list[X] {{cname}}(object o) except *:
 
 cimport cython
 
-cdef extern from *:
-    ctypedef struct X "{{T0}}":
-        pass
-    cdef object X_to_py "{{T0_to_py}}" (X)
+{{template_type_declarations}}
 
 cdef extern from *:
     cdef cppclass cpp_list "std::list" [T]:
@@ -113,10 +101,7 @@ cdef object {{cname}}(const_cpp_list[X]& v):
 
 #################### set.from_py ####################
 
-cdef extern from *:
-    ctypedef struct X "{{T0}}":
-        pass
-    cdef X X_from_py "{{T0_from_py}}" (object) except *
+{{template_type_declarations}}
 
 cdef extern from *:
     cdef cppclass set "std::set" [T]:
@@ -134,10 +119,7 @@ cdef set[X] {{cname}}(object o) except *:
 
 cimport cython
 
-cdef extern from *:
-    ctypedef struct X "{{T0}}":
-        pass
-    cdef object X_to_py "{{T0_to_py}}" (X)
+{{template_type_declarations}}
 
 cdef extern from *:
     cdef cppclass cpp_set "std::set" [T]:
@@ -161,13 +143,7 @@ cdef object {{cname}}(const_cpp_set[X]& s):
 
 #################### pair.from_py ####################
 
-cdef extern from *:
-    ctypedef struct X "{{T0}}":
-        pass
-    ctypedef struct Y "{{T1}}":
-        pass
-    cdef X X_from_py "{{T0_from_py}}" (object) except *
-    cdef Y Y_from_py "{{T1_from_py}}" (object) except *
+{{template_type_declarations}}
 
 cdef extern from *:
     cdef cppclass pair "std::pair" [T, U]:
@@ -181,13 +157,7 @@ cdef pair[X,Y] {{cname}}(object o) except *:
 
 #################### pair.to_py ####################
 
-cdef extern from *:
-    ctypedef struct X "{{T0}}":
-        pass
-    ctypedef struct Y "{{T1}}":
-        pass
-    cdef object X_to_py "{{T0_to_py}}" (X)
-    cdef object Y_to_py "{{T1_to_py}}" (Y)
+{{template_type_declarations}}
 
 cdef extern from *:
     cdef cppclass pair "const std::pair" [T, U]:
@@ -201,13 +171,7 @@ cdef object {{cname}}(pair[X,Y]& p):
 
 #################### map.from_py ####################
 
-cdef extern from *:
-    ctypedef struct X "{{T0}}":
-        pass
-    ctypedef struct Y "{{T1}}":
-        pass
-    cdef X X_from_py "{{T0_from_py}}" (object) except *
-    cdef Y Y_from_py "{{T1_from_py}}" (object) except *
+{{template_type_declarations}}
 
 cdef extern from *:
     cdef cppclass pair "std::pair" [T, U]:
@@ -236,13 +200,7 @@ cdef map[X,Y] {{cname}}(object o) except *:
 
 cimport cython
 
-cdef extern from *:
-    ctypedef struct X "{{T0}}":
-        pass
-    ctypedef struct Y "{{T1}}":
-        pass
-    cdef object X_to_py "{{T0_to_py}}" (X)
-    cdef object Y_to_py "{{T1_to_py}}" (Y)
+{{template_type_declarations}}
 
 cdef extern from *:
     cdef cppclass map "std::map" [T, U]: