Implement methods.

artiq/compiler/builtins.py

@@ -205,4 +205,5 @@ def is_allocated(typ):
         accum or not (is_none(typ) or is_bool(typ) or is_int(typ) or
                       is_float(typ) or is_range(typ) or
                       types.is_c_function(typ) or types.is_rpc_function(typ) or
+                      types.is_method(typ) or
                       types.is_value(typ)))

artiq/compiler/transforms/artiq_ir_generator.py

@@ -711,13 +711,22 @@ class ARTIQIRGenerator(algorithm.Visitor):
         finally:
             self.current_assign = old_assign
 
-        if node.attr not in node.type.find().attributes:
+        if node.attr not in obj.type.find().attributes:
             # A class attribute. Get the constructor (class object) and
             # extract the attribute from it.
-            constructor = obj.type.constructor
+            print(node)
-            obj = self.append(ir.GetConstructor(self._env_for(constructor.name),
+            print(obj)
-                                                constructor.name, constructor,
+            constr_type = obj.type.constructor
-                                                name="constructor." + constructor.name))
+            constr = self.append(ir.GetConstructor(self._env_for(constr_type.name),
+                                                   constr_type.name, constr_type,
+                                                   name="constructor." + constr_type.name))
+
+            if types.is_function(constr.type.attributes[node.attr]):
+                # A method. Construct a method object instead.
+                func = self.append(ir.GetAttr(constr, node.attr))
+                return self.append(ir.Alloc([func, obj], node.type))
+            else:
+                obj = constr
 
         if self.current_assign is None:
             return self.append(ir.GetAttr(obj, node.attr,
@@ -1413,36 +1422,49 @@ class ARTIQIRGenerator(algorithm.Visitor):
         elif types.is_builtin(typ):
             return self.visit_builtin_call(node)
         else:
-            func = self.visit(node.func)
+            if types.is_function(typ):
-            args = [None] * (len(typ.args) + len(typ.optargs))
+                func     = self.visit(node.func)
+                self_arg = None
+                fn_typ   = typ
+            elif types.is_method(typ):
+                method   = self.visit(node.func)
+                func     = self.append(ir.GetAttr(method, "__func__"))
+                self_arg = self.append(ir.GetAttr(method, "__self__"))
+                fn_typ   = types.get_method_function(typ)
+
+            args = [None] * (len(fn_typ.args) + len(fn_typ.optargs))
 
             for index, arg_node in enumerate(node.args):
                 arg = self.visit(arg_node)
-                if index < len(typ.args):
+                if index < len(fn_typ.args):
                     args[index] = arg
                 else:
                     args[index] = self.append(ir.Alloc([arg], ir.TOption(arg.type)))
 
             for keyword in node.keywords:
                 arg = self.visit(keyword.value)
-                if keyword.arg in typ.args:
+                if keyword.arg in fn_typ.args:
-                    for index, arg_name in enumerate(typ.args):
+                    for index, arg_name in enumerate(fn_typ.args):
                         if keyword.arg == arg_name:
                             assert args[index] is None
                             args[index] = arg
                             break
-                elif keyword.arg in typ.optargs:
+                elif keyword.arg in fn_typ.optargs:
-                    for index, optarg_name in enumerate(typ.optargs):
+                    for index, optarg_name in enumerate(fn_typ.optargs):
                         if keyword.arg == optarg_name:
-                            assert args[len(typ.args) + index] is None
+                            assert args[len(fn_typ.args) + index] is None
-                            args[len(typ.args) + index] = \
+                            args[len(fn_typ.args) + index] = \
                                     self.append(ir.Alloc([arg], ir.TOption(arg.type)))
                             break
 
-            for index, optarg_name in enumerate(typ.optargs):
+            for index, optarg_name in enumerate(fn_typ.optargs):
-                if args[len(typ.args) + index] is None:
+                if args[len(fn_typ.args) + index] is None:
-                    args[len(typ.args) + index] = \
+                    args[len(fn_typ.args) + index] = \
-                            self.append(ir.Alloc([], ir.TOption(typ.optargs[optarg_name])))
+                            self.append(ir.Alloc([], ir.TOption(fn_typ.optargs[optarg_name])))
+
+            if self_arg is not None:
+                assert args[0] is None
+                args[0] = self_arg
 
             assert None not in args
 

artiq/compiler/transforms/inferencer.py

@@ -22,7 +22,7 @@ class Inferencer(algorithm.Visitor):
         self.in_loop = False
         self.has_return = False
 
-    def _unify(self, typea, typeb, loca, locb, makenotes=None):
+    def _unify(self, typea, typeb, loca, locb, makenotes=None, when=""):
         try:
             typea.unify(typeb)
         except types.UnificationError as e:
@@ -45,16 +45,19 @@ class Inferencer(algorithm.Visitor):
                             locb))
 
             highlights = [locb] if locb else []
-            if e.typea.find() == typea.find() and e.typeb.find() == typeb.find():
+            if e.typea.find() == typea.find() and e.typeb.find() == typeb.find() or \
+                    e.typeb.find() == typea.find() and e.typea.find() == typeb.find():
                 diag = diagnostic.Diagnostic("error",
-                    "cannot unify {typea} with {typeb}",
+                    "cannot unify {typea} with {typeb}{when}",
-                    {"typea": printer.name(typea), "typeb": printer.name(typeb)},
+                    {"typea": printer.name(typea), "typeb": printer.name(typeb),
+                     "when": when},
                     loca, highlights, notes)
             else: # give more detail
                 diag = diagnostic.Diagnostic("error",
-                    "cannot unify {typea} with {typeb}: {fraga} is incompatible with {fragb}",
+                    "cannot unify {typea} with {typeb}{when}: {fraga} is incompatible with {fragb}",
                     {"typea": printer.name(typea),   "typeb": printer.name(typeb),
-                     "fraga": printer.name(e.typea), "fragb": printer.name(e.typeb)},
+                     "fraga": printer.name(e.typea), "fragb": printer.name(e.typeb),
+                      "when": when},
                     loca, highlights, notes)
             self.engine.process(diag)
 
@@ -88,13 +91,43 @@ class Inferencer(algorithm.Visitor):
         object_type = node.value.type.find()
         if not types.is_var(object_type):
             if node.attr in object_type.attributes:
-                # assumes no free type variables in .attributes
+                # Assumes no free type variables in .attributes.
                 self._unify(node.type, object_type.attributes[node.attr],
                             node.loc, None)
             elif types.is_instance(object_type) and \
                     node.attr in object_type.constructor.attributes:
-                # assumes no free type variables in .attributes
+                # Assumes no free type variables in .attributes.
-                self._unify(node.type, object_type.constructor.attributes[node.attr],
+                attr_type = object_type.constructor.attributes[node.attr].find()
+                if types.is_function(attr_type):
+                    # Convert to a method.
+                    if len(attr_type.args) < 1:
+                        diag = diagnostic.Diagnostic("error",
+                            "function '{attr}{type}' of class '{class}' cannot accept a self argument",
+                            {"attr": node.attr, "type": types.TypePrinter().name(attr_type),
+                             "class": object_type.name},
+                            node.loc)
+                        self.engine.process(diag)
+                        return
+                    else:
+                        def makenotes(printer, typea, typeb, loca, locb):
+                            return [
+                                diagnostic.Diagnostic("note",
+                                    "expression of type {typea}",
+                                    {"typea": printer.name(typea)},
+                                    loca),
+                                diagnostic.Diagnostic("note",
+                                    "reference to a class function of type {typeb}",
+                                    {"typeb": printer.name(attr_type)},
+                                    locb)
+                            ]
+
+                        self._unify(object_type, list(attr_type.args.values())[0],
+                                    node.value.loc, node.loc,
+                                    makenotes=makenotes,
+                                    when=" while inferring the type for self argument")
+
+                    attr_type = types.TMethod(object_type, attr_type)
+                self._unify(node.type, attr_type,
                             node.loc, None)
             else:
                 diag = diagnostic.Diagnostic("error",
@@ -695,7 +728,7 @@ class Inferencer(algorithm.Visitor):
             return
         elif types.is_builtin(typ):
             return self.visit_builtin_call(node)
-        elif not types.is_function(typ):
+        elif not (types.is_function(typ) or types.is_method(typ)):
             diag = diagnostic.Diagnostic("error",
                 "cannot call this expression of type {type}",
                 {"type": types.TypePrinter().name(typ)},
@@ -703,22 +736,34 @@ class Inferencer(algorithm.Visitor):
             self.engine.process(diag)
             return
 
+        if types.is_function(typ):
+            typ_arity   = typ.arity()
+            typ_args    = typ.args
+            typ_optargs = typ.optargs
+            typ_ret     = typ.ret
+        else:
+            typ         = types.get_method_function(typ)
+            typ_arity   = typ.arity() - 1
+            typ_args    = OrderedDict(list(typ.args.items())[1:])
+            typ_optargs = typ.optargs
+            typ_ret     = typ.ret
+
         passed_args = dict()
 
-        if len(node.args) > typ.arity():
+        if len(node.args) > typ_arity:
             note = diagnostic.Diagnostic("note",
                 "extraneous argument(s)", {},
-                node.args[typ.arity()].loc.join(node.args[-1].loc))
+                node.args[typ_arity].loc.join(node.args[-1].loc))
             diag = diagnostic.Diagnostic("error",
                 "this function of type {type} accepts at most {num} arguments",
                 {"type": types.TypePrinter().name(node.func.type),
-                 "num": typ.arity()},
+                 "num": typ_arity},
                 node.func.loc, [], [note])
             self.engine.process(diag)
             return
 
         for actualarg, (formalname, formaltyp) in \
-                zip(node.args, list(typ.args.items()) + list(typ.optargs.items())):
+                zip(node.args, list(typ_args.items()) + list(typ_optargs.items())):
             self._unify(actualarg.type, formaltyp,
                         actualarg.loc, None)
             passed_args[formalname] = actualarg.loc
@@ -732,15 +777,15 @@ class Inferencer(algorithm.Visitor):
                 self.engine.process(diag)
                 return
 
-            if keyword.arg in typ.args:
+            if keyword.arg in typ_args:
-                self._unify(keyword.value.type, typ.args[keyword.arg],
+                self._unify(keyword.value.type, typ_args[keyword.arg],
                             keyword.value.loc, None)
-            elif keyword.arg in typ.optargs:
+            elif keyword.arg in typ_optargs:
-                self._unify(keyword.value.type, typ.optargs[keyword.arg],
+                self._unify(keyword.value.type, typ_optargs[keyword.arg],
                             keyword.value.loc, None)
             passed_args[keyword.arg] = keyword.arg_loc
 
-        for formalname in typ.args:
+        for formalname in typ_args:
             if formalname not in passed_args:
                 note = diagnostic.Diagnostic("note",
                     "the called function is of type {type}",
@@ -753,7 +798,7 @@ class Inferencer(algorithm.Visitor):
                 self.engine.process(diag)
                 return
 
-        self._unify(node.type, typ.ret,
+        self._unify(node.type, typ_ret,
                     node.loc, None)
 
     def visit_LambdaT(self, node):

artiq/compiler/transforms/llvm_ir_generator.py

@@ -192,6 +192,10 @@ class LLVMIRGenerator:
                 return llty
             else:
                 return ll.LiteralStructType([envarg, llty.as_pointer()])
+        elif types.is_method(typ):
+            llfuncty = self.llty_of_type(types.get_method_function(typ))
+            llselfty = self.llty_of_type(types.get_method_self(typ))
+            return ll.LiteralStructType([llfuncty, llselfty])
         elif builtins.is_none(typ):
             if for_return:
                 return llvoid

artiq/compiler/types.py

@@ -350,9 +350,20 @@ class TInstance(TMono):
         self.attributes = attributes
 
     def __repr__(self):
-        return "py2llvm.types.TInstance({}, {]})".format(
+        return "py2llvm.types.TInstance({}, {})".format(
                     repr(self.name), repr(self.attributes))
 
+class TMethod(TMono):
+    """
+    A type of a method.
+    """
+
+    def __init__(self, self_type, function_type):
+        super().__init__("method", {"self": self_type, "fn": function_type})
+        self.attributes = OrderedDict([
+            ("__func__", function_type),
+            ("__self__", self_type),
+        ])
 
 class TValue(Type):
     """
@@ -452,6 +463,17 @@ def is_instance(typ, name=None):
     else:
         return isinstance(typ, TInstance)
 
+def is_method(typ):
+    return isinstance(typ.find(), TMethod)
+
+def get_method_self(typ):
+    if is_method(typ):
+        return typ.find().params["self"]
+
+def get_method_function(typ):
+    if is_method(typ):
+        return typ.find().params["fn"]
+
 def is_value(typ):
     return isinstance(typ.find(), TValue)
 

lit-test/test/inferencer/class.py

@@ -5,10 +5,15 @@ class c:
     a = 1
     def f():
         pass
+    def m(self):
+        pass
 
-# CHECK-L: c:<constructor c {a: int(width='a), f: ()->NoneType}>
+# CHECK-L: c:<constructor c {a: int(width='a), f: ()->NoneType, m: (self:c)->NoneType}>
 c
 # CHECK-L: .a:int(width='a)
 c.a
 # CHECK-L: .f:()->NoneType
 c.f
+
+# CHECK-L: .m:method(self=c, fn=(self:c)->NoneType)
+c().m()

lit-test/test/inferencer/error_method.py

@@ -0,0 +1,16 @@
+# RUN: %python -m artiq.compiler.testbench.inferencer +diag %s >%t
+# RUN: OutputCheck %s --file-to-check=%t
+
+class c:
+    def f():
+        pass
+
+    def g(self):
+        pass
+
+# CHECK-L: ${LINE:+1}: error: function 'f()->NoneType' of class 'c' cannot accept a self argument
+c().f()
+
+c.g(1)
+# CHECK-L: ${LINE:+1}: error: cannot unify c with int(width='a) while inferring the type for self argument
+c().g()

lit-test/test/integration/class.py

@@ -5,6 +5,9 @@ class c:
     a = 1
     def f():
         return 2
+    def g(self):
+        return self.a + 5
 
 assert c.a == 1
 assert c.f() == 2
+assert c().g() == 6