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rt/include/python/basedef.hpp

+//
+// Created by Tom on 24/03/2023.
+//
+
+#ifndef TYPON_BASEDEF_HPP
+#define TYPON_BASEDEF_HPP
+
+template<typename Self>
+class TyBuiltin {
+  template <typename... Args>
+  auto sync_wrapper(Args&&... args)
+  {
+    return static_cast<Self*>(this)->sync(std::forward<Args>(args)...);
+  }
+
+public:
+  template <typename... Args>
+  auto operator()(Args&&... args) -> decltype(sync_wrapper(std::forward<Args>(args)...))
+  {
+    return sync_wrapper(std::forward<Args>(args)...);
+  }
+};
+
+#endif // TYPON_BASEDEF_HPP

rt/include/python/builtins.hpp

@@ -11,6 +11,7 @@
 #include <string>
 
 #include <typon/typon.hpp>
+#include <python/basedef.hpp>
 
 #ifdef __cpp_lib_unreachable
 #include <utility>

rt/include/python/builtins/range.hpp

@@ -7,25 +7,16 @@
 
 #include <ranges>
 
-#include <typon/typon.hpp>
+#include <python/basedef.hpp>
 
 // todo: proper range support
-struct {
-  template <typename T> auto sync(T stop) { return std::views::iota(0, stop); }
-
-  template <typename T> auto sync(T start, T stop) {
-    return std::views::iota(start, stop);
-  }
-
+struct range_s : TyBuiltin<range_s>
+{
   template <typename T>
-  auto operator()(T stop) -> typon::Task<decltype(sync(stop))> {
-    co_return sync(stop);
-  }
+  auto sync(T stop) { return std::views::iota(0, stop); }
 
   template <typename T>
-  auto operator()(T start, T stop) -> typon::Task<decltype(sync(start, stop))> {
-    co_return sync(start, stop);
-  }
+  auto sync(T start, T stop) { return std::views::iota(start, stop); }
 } range;
 
 #endif // TYPON_RANGE_HPP

trans/.env.example

+ALT_RUNNER="clang++-16 -O3 -Wno-return-type -Wno-unused-result -I../rt/include -std=c++20 -o {name_bin} {name_cpp_posix} -pthread -luring && {name_bin}"
\ No newline at end of file

trans/.gitignore

-__pycache__
+__pycache__
\ No newline at end of file
+.env
\ No newline at end of file

trans/requirements.txt

 clang-format==15.0.7

trans/stdlib/__init__.py

+from typing import Self, TypeVar, Generic
+
+
+class int:
+    def __add__(self, other: Self) -> Self: ...
+
+    def __sub__(self, other: Self) -> Self: ...
+
+    def __mul__(self, other: Self) -> Self: ...
+
+    def __and__(self, other: Self) -> Self: ...
+
+
+U = TypeVar("U")
+
+
+class list(Generic[U]):
+
+    def __add__(self, other: Self) -> Self: ...
+
+    def __mul__(self, other: int) -> Self: ...
+
+    def first(self) -> U: ...
+
+
+def print(*args) -> None: ...

trans/stdlib/sys.py

+stdout: CppType["auto&"]

trans/typon/__init__.py → trans/stdlib/typon/__init__.py

-from typing import Callable, TypeVar
+from typing import Callable, TypeVar, Generic
 
 T = TypeVar("T")
 
+class Fork(Generic[T]):
+   def get(self) -> T: ...
 
-def fork(f: Callable[[], T]) -> T:
+
+def fork(f: Callable[[], T]) -> Fork[T]:
     # stub
-    return f()
+    class Res:
+        get = f
+    return Res
 
 
 def future(f: Callable[[], T]) -> T:
@@ -13,10 +18,10 @@ def future(f: Callable[[], T]) -> T:
     return f()
 
 
-def sync():
+def sync() -> None:
     # stub
     pass
 
 
-def is_cpp():
+def is_cpp() -> bool:
     return False

trans/test_runner.py

 # coding: utf-8
-from os import system
+from os import system, environ
 from pathlib import Path
 
 from transpiler import transpile
 from transpiler.format import format_code
 
-# print(format_code("int x = 2 + ((3 * 5));;;"))
+# load .env file
+from dotenv import load_dotenv
+
+load_dotenv()
 
 def run_tests():
     for path in Path('tests').glob('*.py'):
@@ -15,22 +18,21 @@ def run_tests():
             continue
         with open(path, "r", encoding="utf-8") as f:
             res = format_code(transpile(f.read()))
+        #print(res)
         name_cpp = path.with_suffix('.cpp')
         with open(name_cpp, "w", encoding="utf-8") as fcpp:
             fcpp.write(res)
         name_bin = path.with_suffix('').as_posix()
-        cmd = f"bash -c 'g++ -I../rt/include -std=c++20 -o {name_bin} {name_cpp.as_posix()}'"
         commands = [
-            cmd,
-            f"bash -c 'PYTHONPATH=. python3 ./{path.as_posix()}'",
-            f"bash -c './{name_bin}'",
-            f"scp ./{name_bin} tom@192.168.139.128:/tmp/{name_bin}",  # TODO: temporary test suite. Will fix.
-            f"bash -c 'ssh tom@192.168.139.128 \"chmod +x /tmp/{name_bin} && /tmp/{name_bin}\"'"
+            f"bash -c 'PYTHONPATH=stdlib python3 ./{path.as_posix()}'",
         ]
+        if alt := environ.get("ALT_RUNNER"):
+            commands.append(alt.format(name_bin=name_bin, name_cpp_posix=name_cpp.as_posix()))
         for cmd in commands:
             if system(cmd) != 0:
                 print(f"Error running command: {cmd}")
                 break
+        #exit()
 
 
 if __name__ == "__main__":

trans/tests/_builtins_test.py → trans/tests/builtins_test.py

@@ -4,27 +4,28 @@ from typon import is_cpp
 import sys as sis
 from sys import stdout as truc
 
+foo = 123
 test = (2 + 3) * 4
 glob = 5
 
-def g():
-    a = 8
-    if True:
-        b = 9
-        if True:
-            c = 10
-            if True:
-                d = a + b + c
-    if True:
-        e = d + 1
-    print(e)
-
-def f(x):
+# def g():
+#     a = 8
+#     if True:
+#         b = 9
+#         if True:
+#             c = 10
+#             if True:
+#                 d = a + b + c
+#     if True:
+#         e = d + 1
+#     print(e)
+
+def f(x: int):
     return x + 1
 
 
 def fct(param):
-    loc = 456
+    loc = f(456)
     global glob
     loc = 789
     glob = 123

trans/tests/naive_fibonacci_accelerated_fork.py

@@ -17,7 +17,7 @@ def parallel_fibo(n: int) -> int:
     x = fork(lambda: fibo(n - 1))
     y = fork(lambda: fibo(n - 2))
     sync()
-    return x + y
+    return x.get() + y.get()
 
 
 if __name__ == "__main__":

trans/tests/naive_fibonacci_fork.py

@@ -6,8 +6,8 @@ def fibo(n: int) -> int:
     a = fork(lambda: fibo(n - 1))
     b = fork(lambda: fibo(n - 2))
     sync()
-    return a + b
+    return a.get() + b.get()
 
 
 if __name__ == "__main__":
-    print(fibo(30)) # should display 832040
+    print(fibo(20)) # should display 832040
\ No newline at end of file

trans/tests/naive_fibonacci_sequential.py

-def fibo(n):
+def fibo(n: int):
     if n < 2:
         return n
     a = fibo(n - 1)

trans/transpiler/__init__.py

@@ -2,10 +2,31 @@
 import ast
 
 from transpiler.consts import MAPPINGS
-from transpiler.scope import Scope
-from transpiler.visitors.file import FileVisitor
+#from transpiler.phases import initial_pytype
+from transpiler.phases.emit_cpp.file import FileVisitor
+from transpiler.phases.if_main import IfMainVisitor
+from transpiler.phases.typing.block import ScoperBlockVisitor
+from transpiler.phases.typing.scope import Scope
 
 
 def transpile(source):
-    tree = ast.parse(source)
-    return "\n".join(filter(None, map(str, FileVisitor(Scope()).visit(tree))))
+    res = ast.parse(source)
+    #res = initial_pytype.run(source, res)
+    IfMainVisitor().visit(res)
+    ScoperBlockVisitor().visit(res)
+    #print(res.scope)
+
+    # display each scope
+    def disp_scope(scope, indent=0):
+        print("  " * indent, scope.kind)
+        for child in scope.children:
+            disp_scope(child, indent + 1)
+        for var in scope.vars.items():
+            print("  " * (indent + 1), var)
+
+
+    #disp_scope(res.scope)
+
+    code = "\n".join(filter(None, map(str, FileVisitor(Scope()).visit(res))))
+    return code
+

trans/transpiler/visitors/__init__.py → trans/transpiler/phases/emit_cpp/__init__.py

 # coding: utf-8
 import ast
-from dataclasses import dataclass
 from enum import Flag
-from itertools import zip_longest, chain
-from typing import Iterable, Union
+from itertools import chain
+from typing import Iterable
 
-from transpiler import MAPPINGS
+from transpiler.phases.emit_cpp.consts import MAPPINGS
+from transpiler.phases.typing import TypeVariable
+from transpiler.phases.typing.types import BaseType, TY_INT, TY_BOOL, ForkResult
+from transpiler.utils import UnsupportedNodeError
 
-
-class NodeVisitor:
+class UniversalVisitor:
     def visit(self, node):
         """Visit a node."""
         if type(node) == list:
@@ -25,6 +26,23 @@ class NodeVisitor:
     def missing_impl(self, node):
         raise UnsupportedNodeError(node)
 
+class TypeVisitor(UniversalVisitor):
+    def visit_TypeVariable(self, node: TypeVariable) -> Iterable[str]:
+        yield str(node)
+        #raise ValueError("Unresolved type variable")
+
+    def visit_BaseType(self, node: BaseType) -> Iterable[str]:
+        node = node.resolve()
+        if node is TY_INT:
+            yield "int"
+        elif node is TY_BOOL:
+            yield "bool"
+        elif isinstance(node, TypeVariable):
+            raise NotImplementedError(f"Not unified type variable {node}")
+        else:
+            raise NotImplementedError(node)
+
+class NodeVisitor(UniversalVisitor):
     def process_args(self, node: ast.arguments) -> (str, str, str):
         for field in ("posonlyargs", "vararg", "kwonlyargs", "kw_defaults", "kwarg", "defaults"):
             if getattr(node, field, None):
@@ -44,14 +62,20 @@ class NodeVisitor:
             return f"py_{name[2:-2]}"
         return MAPPINGS.get(name, name)
 
-
-@dataclass
-class UnsupportedNodeError(Exception):
-    node: ast.AST
-
-    def __str__(self) -> str:
-        return f"Unsupported node: {self.node.__class__.__mro__} {ast.dump(self.node)}"
-
+    def visit_BaseType(self, node: BaseType) -> Iterable[str]:
+        node = node.resolve()
+        if node is TY_INT:
+            yield "int"
+        elif node is TY_BOOL:
+            yield "bool"
+        elif isinstance(node, ForkResult):
+            yield "Forked<"
+            yield from self.visit(node.return_type)
+            yield ">"
+        elif isinstance(node, TypeVariable):
+            raise NotImplementedError(f"Not unified type variable {node}")
+        else:
+            raise NotImplementedError(node)
 
 class CoroutineMode(Flag):
     SYNC = 1
@@ -61,7 +85,6 @@ class CoroutineMode(Flag):
     TASK = 16 | ASYNC
     JOIN = 32 | ASYNC
 
-
 def join(sep: str, items: Iterable[Iterable[str]]) -> Iterable[str]:
     items = iter(items)
     try:
@@ -72,24 +95,5 @@ def join(sep: str, items: Iterable[Iterable[str]]) -> Iterable[str]:
     except StopIteration:
         return
 
-
-def compare_ast(node1: Union[ast.expr, list[ast.expr]], node2: Union[ast.expr, list[ast.expr]]) -> bool:
-    if type(node1) is not type(node2):
-        return False
-
-    if isinstance(node1, ast.AST):
-        for k, v in vars(node1).items():
-            if k in {"lineno", "end_lineno", "col_offset", "end_col_offset", "ctx"}:
-                continue
-            if not compare_ast(v, getattr(node2, k)):
-                return False
-        return True
-
-    elif isinstance(node1, list) and isinstance(node2, list):
-        return all(compare_ast(n1, n2) for n1, n2 in zip_longest(node1, node2))
-    else:
-        return node1 == node2
-
-
 def flatmap(f, items):
-    return chain.from_iterable(map(f, items))
+    return chain.from_iterable(map(f, items))
\ No newline at end of file

trans/transpiler/visitors/block.py → trans/transpiler/phases/emit_cpp/block.py

@@ -3,10 +3,14 @@ import ast
 from dataclasses import dataclass
 from typing import Iterable, Optional
 
-from transpiler.scope import VarDecl, VarKind, Scope
-from transpiler.visitors import CoroutineMode, NodeVisitor, flatmap, compare_ast
-from transpiler.visitors.expr import ExpressionVisitor
-from transpiler.visitors.search import SearchVisitor
+from transpiler.phases.typing.scope import Scope
+from transpiler.phases.typing.types import BaseType, TY_INT, TY_BOOL, TypeVariable
+from transpiler.utils import compare_ast
+from transpiler.phases.emit_cpp import NodeVisitor, CoroutineMode, flatmap
+from transpiler.phases.emit_cpp.expr import ExpressionVisitor
+from transpiler.phases.emit_cpp.search import SearchVisitor
+
+#from transpiler.scope import VarDecl, VarKind, Scope
 
 
 # noinspection PyPep8Naming
@@ -19,6 +23,25 @@ class BlockVisitor(NodeVisitor):
         return ExpressionVisitor(self.scope, self.generator)
 
     def visit_FunctionDef(self, node: ast.FunctionDef) -> Iterable[str]:
+        if getattr(node, "is_main", False):
+            # Special case handling for Python's interesting way of defining an entry point.
+            # I mean, it's not *that* bad, it's just an attempt at retrofitting an "entry point" logic in a scripting
+            # language that, by essence, uses "the start of the file" as the implicit entry point, since files are
+            # read and executed line-by-line, contrary to usual structured languages that mark a distinction between
+            # declarations (functions, classes, modules, ...) and code.
+            # Also, for nitpickers, the C++ standard explicitly allows for omitting a `return` statement in the `main`.
+            # 0 is returned by default.
+            yield "typon::Root root()"
+
+            def block():
+                yield from node.body
+                yield ast.Return()
+
+            from transpiler.phases.emit_cpp.function import FunctionVisitor
+            yield from FunctionVisitor(self.scope, CoroutineMode.TASK).emit_block(node.scope, block())
+            yield "int main() { root().call(); }"
+            return
+
         yield "struct {"
         yield from self.visit_func(node, CoroutineMode.FAKE)
 
@@ -56,7 +79,6 @@ class BlockVisitor(NodeVisitor):
         yield f"}} {node.name};"
 
     def visit_func(self, node: ast.FunctionDef, generator: CoroutineMode) -> Iterable[str]:
-        from transpiler.visitors.function import FunctionVisitor
         templ, args, names = self.process_args(node.args)
         if templ:
             yield "template"
@@ -98,7 +120,8 @@ class BlockVisitor(NodeVisitor):
                 yield "Join"
             yield f"<decltype(sync({', '.join(names)}))>"
         yield "{"
-        inner_scope = self.scope.function(vars={node.name: VarDecl(VarKind.SELF, None)})
+        inner_scope = node.scope
+
         for child in node.body:
             # Python uses module- and function- level scoping. Blocks, like conditionals and loops, do not form scopes
             # on their own. Variables are still accessible in the remainder of the parent function or in the global
@@ -138,23 +161,32 @@ class BlockVisitor(NodeVisitor):
             #     auto y = 2;
             # }
             # ```
-            child_visitor = FunctionVisitor(inner_scope.child(), generator)
-
-            # We need to do this in two-passes. This unfortunately breaks our nice generator state-machine architecture.
-            # Fair enough.
-            [*child_code] = child_visitor.visit(child)
-
-            # Hoist inner variables to the root scope.
-            for var, decl in child_visitor.scope.vars.items():
-                if decl.kind == VarKind.LOCAL:  # Nested declarations become `decltype` declarations.
-                    if getattr(decl.val[1], "in_await", False):
-                        # TODO(zdimension): really?
-                        yield f"decltype({decl.val[0][9:]}.operator co_await().await_resume()) {var};"
-                    else:
-                        yield f"decltype({decl.val[0]}) {var};"
-                elif decl.kind in (VarKind.GLOBAL, VarKind.NONLOCAL):  # `global` and `nonlocal` just get hoisted as-is.
-                    inner_scope.vars[var] = decl
-            yield from child_code  # Yeet back the child node code.
+            from transpiler.phases.emit_cpp.function import FunctionVisitor
+            child_visitor = FunctionVisitor(inner_scope, generator)
+
+            if True:
+                for name, decl in getattr(child, "decls", {}).items():
+                    #yield f"decltype({' '.join(self.expr().visit(decl.type))}) {name};"
+                    yield from self.visit(decl.type)
+                    yield f" {name};"
+                yield from child_visitor.visit(child)
+            else:
+                # We need to do this in two-passes. This unfortunately breaks our nice generator state-machine architecture.
+                # Fair enough.
+                # TODO(zdimension): break this in two visitors
+                [*child_code] = child_visitor.visit(child)
+
+                # Hoist inner variables to the root scope.
+                for var, decl in child_visitor.scope.vars.items():
+                    if decl.kind == VarKind.LOCAL:  # Nested declarations become `decltype` declarations.
+                        if getattr(decl.val[1], "in_await", False):
+                            # TODO(zdimension): really?
+                            yield f"decltype({decl.val[0][9:]}.operator co_await().await_resume()) {var};"
+                        else:
+                            yield f"decltype({decl.val[0]}) {var};"
+                    elif decl.kind in (VarKind.GLOBAL, VarKind.NONLOCAL):  # `global` and `nonlocal` just get hoisted as-is.
+                        inner_scope.vars[var] = decl
+                yield from child_code  # Yeet back the child node code.
         if CoroutineMode.FAKE in generator:
             yield "TYPON_UNREACHABLE();"  # So the compiler doesn't complain about missing return statements.
         elif CoroutineMode.ASYNC in generator and CoroutineMode.GENERATOR not in generator:
@@ -162,15 +194,17 @@ class BlockVisitor(NodeVisitor):
                 yield "co_return;"
         yield "}"
 
-    def visit_lvalue(self, lvalue: ast.expr, val: Optional[ast.AST] = None) -> Iterable[str]:
+    def visit_lvalue(self, lvalue: ast.expr, declare: bool = False) -> Iterable[str]:
         if isinstance(lvalue, ast.Tuple):
             yield f"std::tie({', '.join(flatmap(self.expr().visit, lvalue.elts))})"
         elif isinstance(lvalue, ast.Name):
             name = self.fix_name(lvalue.id)
             # if name not in self._scope.vars:
-            if not self.scope.exists_local(name):
-                yield self.scope.declare(name, (" ".join(self.expr().visit(val)), val) if val else None,
-                                         getattr(val, "is_future", False))
+            # if not self.scope.exists_local(name):
+            #     yield self.scope.declare(name, (" ".join(self.expr().visit(val)), val) if val else None,
+            #                              getattr(val, "is_future", False))
+            if declare:
+                yield from self.visit(lvalue.type)
             yield name
         elif isinstance(lvalue, ast.Subscript):
             yield from self.expr().visit(lvalue)
@@ -180,7 +214,7 @@ class BlockVisitor(NodeVisitor):
     def visit_Assign(self, node: ast.Assign) -> Iterable[str]:
         if len(node.targets) != 1:
             raise NotImplementedError(node)
-        yield from self.visit_lvalue(node.targets[0], node.value)
+        yield from self.visit_lvalue(node.targets[0], node.is_declare)
         yield " = "
         yield from self.expr().visit(node.value)
         yield ";"
@@ -188,7 +222,7 @@ class BlockVisitor(NodeVisitor):
     def visit_AnnAssign(self, node: ast.AnnAssign) -> Iterable[str]:
         if node.value is None:
             raise NotImplementedError(node, "empty value")
-        yield from self.visit_lvalue(node.target, node.value)
+        yield from self.visit_lvalue(node.target)
         yield " = "
         yield from self.expr().visit(node.value)
         yield ";"

trans/transpiler/phases/emit_cpp/consts.py

+# coding: utf-8
+import ast
+
+SYMBOLS = {
+    ast.Eq: "==",
+    ast.NotEq: '!=',
+    ast.Pass: '/* pass */',
+    ast.Mult: '*',
+    ast.Add: '+',
+    ast.Sub: '-',
+    ast.Div: '/',
+    ast.FloorDiv: '/',  # TODO
+    ast.Mod: '%',
+    ast.Lt: '<',
+    ast.Gt: '>',
+    ast.GtE: '>=',
+    ast.LtE: '<=',
+    ast.LShift: '<<',
+    ast.RShift: '>>',
+    ast.BitXor: '^',
+    ast.BitOr: '|',
+    ast.BitAnd: '&',
+    ast.Not: '!',
+    ast.IsNot: '!=',
+    ast.USub: '-',
+    ast.And: '&&',
+    ast.Or: '||'
+}
+"""Mapping of Python AST nodes to C++ symbols."""
+
+PRECEDENCE = [
+    ("()", "[]", ".",),
+    ("unary", "co_await"),
+    ("*", "/", "%",),
+    ("+", "-"),
+    ("<<", ">>"),
+    ("<", "<=", ">", ">="),
+    ("==", "!="),
+    ("&",),
+    ("^",),
+    ("|",),
+    ("&&",),
+    ("||",),
+    ("?:", "co_yield"),
+    (",",)
+]
+"""Precedence of C++ operators."""
+
+PRECEDENCE_LEVELS = {op: i for i, ops in enumerate(PRECEDENCE) for op in ops}
+"""Mapping of C++ operators to their precedence level."""
+
+MAPPINGS = {
+    "True": "true",
+    "False": "false",
+    "None": "nullptr"
+}
+"""Mapping of Python builtin constants to C++ equivalents."""

trans/transpiler/visitors/expr.py → trans/transpiler/phases/emit_cpp/expr.py

@@ -3,9 +3,10 @@ import ast
 from dataclasses import dataclass, field
 from typing import List, Iterable
 
+from transpiler.utils import compare_ast
 from transpiler.consts import SYMBOLS, PRECEDENCE_LEVELS
-from transpiler.scope import VarKind, Scope
-from transpiler.visitors import CoroutineMode, NodeVisitor, join, compare_ast
+from transpiler.phases.emit_cpp import CoroutineMode, join, NodeVisitor
+from transpiler.phases.typing.scope import Scope, VarKind
 
 
 class PrecedenceContext:
@@ -74,7 +75,7 @@ class ExpressionVisitor(NodeVisitor):
 
     def visit_Name(self, node: ast.Name) -> Iterable[str]:
         res = self.fix_name(node.id)
-        if decl := self.scope.get(res):
+        if False and (decl := self.scope.get(res)):
             if decl.kind == VarKind.SELF:
                 res = "(*this)"
             elif decl.future and CoroutineMode.ASYNC in self.generator:

trans/transpiler/visitors/file.py → trans/transpiler/phases/emit_cpp/file.py

@@ -2,8 +2,8 @@
 import ast
 from typing import Iterable
 
-from transpiler.visitors.block import BlockVisitor
-from transpiler.visitors.module import ModuleVisitor
+from transpiler.phases.emit_cpp.block import BlockVisitor
+from transpiler.phases.emit_cpp.module import ModuleVisitor
 
 
 # noinspection PyPep8Naming

trans/transpiler/visitors/function.py → trans/transpiler/phases/emit_cpp/function.py

@@ -4,9 +4,9 @@ from dataclasses import dataclass
 from typing import Iterable
 
 from transpiler.consts import SYMBOLS
-from transpiler.scope import VarDecl, VarKind
-from transpiler.visitors import CoroutineMode
-from transpiler.visitors.block import BlockVisitor
+from transpiler.phases.emit_cpp import CoroutineMode
+from transpiler.phases.emit_cpp.block import BlockVisitor
+from transpiler.phases.typing.scope import Scope
 
 
 # noinspection PyPep8Naming
@@ -17,7 +17,7 @@ class FunctionVisitor(BlockVisitor):
         yield ";"
 
     def visit_AugAssign(self, node: ast.AugAssign) -> Iterable[str]:
-        yield from self.visit_lvalue(node.target)
+        yield from self.visit_lvalue(node.target, False)
         yield SYMBOLS[type(node.op)] + "="
         yield from self.expr().visit(node.value)
         yield ";"
@@ -28,7 +28,7 @@ class FunctionVisitor(BlockVisitor):
         yield f"for (auto {node.target.id} : "
         yield from self.expr().visit(node.iter)
         yield ")"
-        yield from self.emit_block(node.body)
+        yield from self.emit_block(node.scope, node.body)
         if node.orelse:
             raise NotImplementedError(node, "orelse")
 
@@ -36,13 +36,13 @@ class FunctionVisitor(BlockVisitor):
         yield "if ("
         yield from self.expr().visit(node.test)
         yield ")"
-        yield from self.emit_block(node.body)
+        yield from self.emit_block(node.scope, node.body)
         if node.orelse:
             yield "else "
             if isinstance(node.orelse, ast.If):
                 yield from self.visit(node.orelse)
             else:
-                yield from self.emit_block(node.orelse)
+                yield from self.emit_block(node.orelse.scope, node.orelse)
 
     def visit_Return(self, node: ast.Return) -> Iterable[str]:
         if CoroutineMode.ASYNC in self.generator:
@@ -57,29 +57,24 @@ class FunctionVisitor(BlockVisitor):
         yield "while ("
         yield from self.expr().visit(node.test)
         yield ")"
-        yield from self.emit_block(node.body)
+        yield from self.emit_block(node.scope, node.body)
         if node.orelse:
             raise NotImplementedError(node, "orelse")
 
     def visit_Global(self, node: ast.Global) -> Iterable[str]:
-        for name in map(self.fix_name, node.names):
-            self.scope.vars[name] = VarDecl(VarKind.GLOBAL, None)
         yield ""
 
     def visit_Nonlocal(self, node: ast.Nonlocal) -> Iterable[str]:
-        for name in map(self.fix_name, node.names):
-            self.scope.vars[name] = VarDecl(VarKind.NONLOCAL, None)
         yield ""
 
-    def block(self) -> "FunctionVisitor":
+    def block2(self) -> "FunctionVisitor":
         # See the comments in visit_FunctionDef.
         # A Python code block does not introduce a new scope, so we create a new `Scope` object that shares the same
         # variables as the parent scope.
         return FunctionVisitor(self.scope.child_share(), self.generator)
 
-    def emit_block(self, items: Iterable[ast.stmt]) -> Iterable[str]:
+    def emit_block(self, scope: Scope, items: Iterable[ast.stmt]) -> Iterable[str]:
         yield "{"
-        block = self.block()
         for child in items:
-            yield from block.visit(child)
+            yield from FunctionVisitor(scope, self.generator).visit(child)
         yield "}"

trans/transpiler/visitors/module.py → trans/transpiler/phases/emit_cpp/module.py

@@ -2,9 +2,10 @@
 import ast
 from typing import Iterable
 
-from transpiler.visitors import CoroutineMode, compare_ast
-from transpiler.visitors.block import BlockVisitor
-from transpiler.visitors.function import FunctionVisitor
+from transpiler.phases.emit_cpp import CoroutineMode
+from transpiler.phases.emit_cpp.block import BlockVisitor
+from transpiler.phases.emit_cpp.function import FunctionVisitor
+from transpiler.utils import compare_ast
 
 
 # noinspection PyPep8Naming
@@ -27,24 +28,3 @@ class ModuleVisitor(BlockVisitor):
             yield from self.import_module(node.module)
             for alias in node.names:
                 yield f"auto& {alias.asname or alias.name} = py_{node.module}::all.{alias.name};"
-
-    def visit_If(self, node: ast.If) -> Iterable[str]:
-        if not node.orelse and compare_ast(node.test, ast.parse('__name__ == "__main__"', mode="eval").body):
-            # Special case handling for Python's interesting way of defining an entry point.
-            # I mean, it's not *that* bad, it's just an attempt at retrofitting an "entry point" logic in a scripting
-            # language that, by essence, uses "the start of the file" as the implicit entry point, since files are
-            # read and executed line-by-line, contrary to usual structured languages that mark a distinction between
-            # declarations (functions, classes, modules, ...) and code.
-            # Also, for nitpickers, the C++ standard explicitly allows for omitting a `return` statement in the `main`.
-            # 0 is returned by default.
-            yield "typon::Root root()"
-
-            def block():
-                yield from node.body
-                yield ast.Return()
-
-            yield from FunctionVisitor(self.scope.function(), CoroutineMode.TASK).emit_block(block())
-            yield "int main() { root().call(); }"
-            return
-
-        raise NotImplementedError(node, "global scope if")

trans/transpiler/visitors/search.py → trans/transpiler/phases/emit_cpp/search.py

 # coding: utf-8
 import ast
 
-from transpiler.visitors import NodeVisitor
+from transpiler.phases.emit_cpp import NodeVisitor
 
 
 class SearchVisitor(NodeVisitor):

trans/transpiler/phases/if_main/__init__.py

+import ast
+
+from transpiler.utils import compare_ast
+
+NAME_MAIN = ast.parse('__name__ == "__main__"', mode="eval").body
+
+class IfMainVisitor(ast.NodeVisitor):
+    def visit_Module(self, node: ast.Module):
+        for i, stmt in enumerate(node.body):
+            if isinstance(stmt, ast.If):
+                if not stmt.orelse and compare_ast(stmt.test, NAME_MAIN):
+                    new_node = ast.FunctionDef(
+                        name="main",
+                        args=ast.arguments(args=[]),
+                        body=stmt.body,
+                        decorator_list=[],
+                        returns=None
+                    )
+                    new_node.is_main = True
+                    node.body[i] = new_node
+                    return
\ No newline at end of file

trans/transpiler/phases/initial_pytype/__init__.py

+import ast
+
+import pytype.config
+from pytype import io
+from pytype.pytd import pytd_utils
+from pytype.tools.traces import traces
+
+
+def run(source: str, module: ast.Module) -> ast.Module:
+    opt = pytype.config.Options.create(None, no_return_any=True, precise_return=True)
+    source_code = infer_types(source, opt)
+
+    visitor = AnnotateAstVisitor(source_code, ast)
+    visitor.visit(module)
+    return module
+
+
+def infer_types(source: str, options: pytype.config.Options) -> "source.Code":
+    with io.wrap_pytype_exceptions(PytypeError, filename=options.input):
+        return traces.trace(source, options)
+
+
+class AnnotateAstVisitor(traces.MatchAstVisitor):
+    def visit_Name(self, node):
+        self._maybe_annotate(node)
+
+    def visit_Attribute(self, node):
+        self._maybe_annotate(node)
+
+    def visit_FunctionDef(self, node):
+        self._maybe_annotate(node)
+
+    def _maybe_annotate(self, node):
+        """Annotates a node."""
+        try:
+            ops = self.match(node)
+        except NotImplementedError:
+            return
+        # For lack of a better option, take the first one.
+        unused_loc, entry = next(iter(ops), (None, None))
+        self._maybe_set_type(node, entry)
+
+    def _maybe_set_type(self, node, trace):
+        """Sets type information on the node, if there is any to set."""
+        if not trace:
+            return
+        node.resolved_type = trace.types[-1]
+        node.resolved_annotation = _annotation_str_from_type_def(trace.types[-1])
+
+
+class PytypeError(Exception):
+    """Wrap exceptions raised by Pytype."""
+
+
+def _annotation_str_from_type_def(type_def):
+    return pytd_utils.Print(type_def)

trans/transpiler/phases/typing/__init__.py

+import ast
+from pathlib import Path
+
+from transpiler.phases.typing.scope import VarKind, VarDecl, ScopeKind
+from transpiler.phases.typing.stdlib import PRELUDE, StdlibVisitor
+from transpiler.phases.typing.types import TY_TYPE, TY_INT, TY_STR, TY_BOOL, TY_COMPLEX, TY_NONE, FunctionType, \
+    TypeVariable, TY_MODULE, CppType, PyList, TypeType, ForkResult
+
+PRELUDE.vars.update({
+    # "int": VarDecl(VarKind.LOCAL, TY_TYPE, TY_INT),
+    # "str": VarDecl(VarKind.LOCAL, TY_TYPE, TY_STR),
+    # "bool": VarDecl(VarKind.LOCAL, TY_TYPE, TY_BOOL),
+    # "complex": VarDecl(VarKind.LOCAL, TY_TYPE, TY_COMPLEX),
+    # "None": VarDecl(VarKind.LOCAL, TY_NONE, None),
+    # "Callable": VarDecl(VarKind.LOCAL, TY_TYPE, FunctionType),
+    # "TypeVar": VarDecl(VarKind.LOCAL, TY_TYPE, TypeVariable),
+    # "CppType": VarDecl(VarKind.LOCAL, TY_TYPE, CppType),
+    # "list": VarDecl(VarKind.LOCAL, TY_TYPE, PyList),
+    "int": VarDecl(VarKind.LOCAL, TypeType(TY_INT)),
+    "str": VarDecl(VarKind.LOCAL, TypeType(TY_STR)),
+    "bool": VarDecl(VarKind.LOCAL, TypeType(TY_BOOL)),
+    "complex": VarDecl(VarKind.LOCAL, TypeType(TY_COMPLEX)),
+    "None": VarDecl(VarKind.LOCAL, TypeType(TY_NONE)),
+    "Callable": VarDecl(VarKind.LOCAL, FunctionType),
+    "TypeVar": VarDecl(VarKind.LOCAL, TypeVariable),
+    "CppType": VarDecl(VarKind.LOCAL, CppType),
+    "list": VarDecl(VarKind.LOCAL, PyList),
+    "Fork": VarDecl(VarKind.LOCAL, ForkResult),
+})
+
+typon_std = Path(__file__).parent.parent.parent.parent / "stdlib"
+
+
+def discover_module(path: Path, scope):
+    for child in path.iterdir():
+        if child.is_dir():
+            mod_scope = PRELUDE.child(ScopeKind.GLOBAL)
+            discover_module(child, mod_scope)
+            scope.vars[child.name] = VarDecl(VarKind.LOCAL, TY_MODULE, {k: v.type for k, v in mod_scope.vars.items()})
+        elif child.name == "__init__.py":
+            StdlibVisitor(scope).visit(ast.parse(child.read_text()))
+            print(f"Visited {child}")
+        elif child.suffix == ".py":
+            mod_scope = PRELUDE.child(ScopeKind.GLOBAL)
+            StdlibVisitor(mod_scope).visit(ast.parse(child.read_text()))
+            scope.vars[child.stem] = VarDecl(VarKind.LOCAL, TY_MODULE, {k: v.type for k, v in mod_scope.vars.items()})
+
+
+discover_module(typon_std, PRELUDE)
+
+print("Stdlib visited!")

trans/transpiler/phases/typing/annotations.py

+import ast
+from dataclasses import dataclass
+from typing import Optional, List
+
+from transpiler.phases.typing.scope import Scope
+from transpiler.phases.typing.types import BaseType, TY_NONE, TypeType, TY_SELF
+from transpiler.phases.utils import NodeVisitorSeq
+
+
+@dataclass
+class TypeAnnotationVisitor(NodeVisitorSeq):
+    scope: Scope
+    cur_class: Optional[TypeType] = None
+
+    def visit_str(self, node: str) -> BaseType:
+        if node in ("Self", "self") and self.cur_class:
+            return TY_SELF
+        if existing := self.scope.get(node):
+            ty = existing.type
+            if isinstance(ty, TypeType):
+                return ty.type_object
+            return ty
+
+        raise NameError(node)
+
+    def visit_Name(self, node: ast.Name) -> BaseType:
+        return self.visit_str(node.id)
+
+    def visit_Constant(self, node: ast.Constant) -> BaseType:
+        if node.value is None:
+            return TY_NONE
+        if type(node.value) == str:
+            return node.value
+        raise NotImplementedError
+
+    def visit_Subscript(self, node: ast.Subscript) -> BaseType:
+        ty_op = self.visit(node.value)
+        args = list(node.slice.elts) if type(node.slice) == ast.Tuple else [node.slice]
+        args = [self.visit(arg) for arg in args]
+        return ty_op(*args)
+        # return TypeOperator([self.visit(node.value)], self.visit(node.slice.value))
+
+    def visit_List(self, node: ast.List) -> List[BaseType]:
+        return [self.visit(elt) for elt in node.elts]

trans/transpiler/phases/typing/block.py

+import ast
+from dataclasses import dataclass
+from typing import Optional
+
+from transpiler.phases.typing.annotations import TypeAnnotationVisitor
+from transpiler.phases.typing.common import ScoperVisitor
+from transpiler.phases.typing.expr import ScoperExprVisitor
+from transpiler.phases.typing.scope import VarDecl, VarKind, ScopeKind
+from transpiler.phases.typing.types import BaseType, TypeVariable, FunctionType, IncompatibleTypesError, TY_MODULE
+
+
+@dataclass
+class ScoperBlockVisitor(ScoperVisitor):
+    stdlib: bool = False
+
+    def expr(self) -> ScoperExprVisitor:
+        return ScoperExprVisitor(self.scope, self.root_decls)
+
+    def visit_Import(self, node: ast.Import):
+        for alias in node.names:
+            self.scope.vars[alias.asname or alias.name] = VarDecl(VarKind.LOCAL, None)
+
+    def visit_ImportFrom(self, node: ast.ImportFrom):
+        module = self.scope.get(node.module)
+        if not module:
+            raise NameError(node.module)
+        if module.type is not TY_MODULE:
+            raise IncompatibleTypesError(f"{node.module} is not a module")
+        for alias in node.names:
+            thing = module.val.get(alias.name)
+            if not thing:
+                raise NameError(alias.name)
+            self.scope.vars[alias.asname or alias.name] = VarDecl(VarKind.LOCAL, thing)
+
+    def visit_Module(self, node: ast.Module):
+        for stmt in node.body:
+            self.visit(stmt)
+
+    def get_type(self, node: ast.expr) -> BaseType:
+        if type := getattr(node, "type", None):
+            return type
+        self.expr().visit(node)
+        return node.type
+        # ntype = TypeVariable()
+        # node.type = ntype
+        # return ntype
+
+    def visit_Assign(self, node: ast.Assign):
+        if len(node.targets) != 1:
+            raise NotImplementedError(node)
+        target = node.targets[0]
+        ty = self.get_type(node.value)
+        target.type = ty
+        node.is_declare = self.visit_assign_target(target, ty)
+
+    def visit_assign_target(self, target, decl_val: BaseType) -> bool:
+        if isinstance(target, ast.Name):
+            if vdecl := self.scope.get(target.id):
+                vdecl.type.unify(decl_val)
+                return False
+            else:
+                self.scope.vars[target.id] = VarDecl(VarKind.LOCAL, decl_val)
+                if self.scope.kind == ScopeKind.FUNCTION_INNER:
+                    self.root_decls[target.id] = VarDecl(VarKind.OUTER_DECL, decl_val)
+                return True
+        else:
+            raise NotImplementedError(target)
+
+    def anno(self) -> "TypeAnnotationVisitor":
+        return TypeAnnotationVisitor(self.scope)
+
+    def visit_annotation(self, expr: Optional[ast.expr]) -> BaseType:
+        return self.anno().visit(expr) if expr else TypeVariable()
+
+    def visit_FunctionDef(self, node: ast.FunctionDef):
+        argtypes = [self.visit_annotation(arg.annotation) for arg in node.args.args]
+        rtype = self.visit_annotation(node.returns)
+        ftype = FunctionType(argtypes, rtype)
+        self.scope.vars[node.name] = VarDecl(VarKind.LOCAL, ftype)
+        scope = self.scope.child(ScopeKind.FUNCTION)
+        scope.obj_type = ftype
+        scope.function = scope
+        node.scope = scope
+        for arg, ty in zip(node.args.args, argtypes):
+            scope.vars[arg.arg] = VarDecl(VarKind.LOCAL, ty)
+        for b in node.body:
+            decls = {}
+            visitor = ScoperBlockVisitor(scope, decls)
+            visitor.visit(b)
+            b.decls = decls
+
+    def visit_If(self, node: ast.If):
+        scope = self.scope.child(ScopeKind.FUNCTION_INNER)
+        scope.function = self.scope.function
+        node.scope = scope
+        visitor = ScoperBlockVisitor(scope, self.root_decls)
+        for b in node.body:
+            visitor.visit(b)
+
+    def visit_Expr(self, node: ast.Expr):
+        self.expr().visit(node.value)
+
+    def visit_Return(self, node: ast.Return):
+        fct = self.scope.function
+        if fct is None:
+            raise IncompatibleTypesError("Return outside function")
+        ftype = fct.obj_type
+        assert isinstance(ftype, FunctionType)
+        vtype = self.expr().visit(node.value) if node.value else None
+        vtype.unify(ftype.return_type)
+
+    def visit_Global(self, node: ast.Global):
+        for name in node.names:
+            self.scope.function.vars[name] = VarDecl(VarKind.GLOBAL, None)
+            if name not in self.scope.global_scope.vars:
+                self.scope.global_scope.vars[name] = VarDecl(VarKind.LOCAL, None)
+
+    def visit_AugAssign(self, node: ast.AugAssign):
+        equivalent = ast.Assign(targets=[node.target], value=ast.BinOp(left=node.target, op=node.op, right=node.value))
+        self.visit(equivalent)
+
+    def visit(self, node: ast.AST):
+        if isinstance(node, ast.AST):
+            super().visit(node)
+            node.scope = self.scope

trans/transpiler/phases/typing/common.py

+from dataclasses import dataclass, field
+from typing import Dict
+
+from transpiler.phases.typing.scope import Scope, ScopeKind, VarDecl
+from transpiler.phases.utils import NodeVisitorSeq
+
+PRELUDE = Scope.make_global()
+
+@dataclass
+class ScoperVisitor(NodeVisitorSeq):
+    scope: Scope = field(default_factory=lambda: PRELUDE.child(ScopeKind.GLOBAL))
+    root_decls: Dict[str, VarDecl] = field(default_factory=dict)
\ No newline at end of file

trans/transpiler/phases/typing/expr.py

+import ast
+from typing import List
+
+from transpiler.phases.typing import ScopeKind, VarDecl, VarKind
+from transpiler.phases.typing.common import ScoperVisitor
+from transpiler.phases.typing.types import IncompatibleTypesError, BaseType, TupleType, TY_STR, TY_BOOL, TY_INT, \
+    TY_COMPLEX, TY_NONE, FunctionType, PyList, TypeVariable, PySet, TypeType, PyDict
+
+DUNDER = {
+    ast.Eq: "eq",
+    ast.NotEq: "ne",
+    ast.Mult: "mul",
+    ast.Add: "add",
+    ast.Sub: "sub",
+    ast.Div: "truediv",
+    ast.FloorDiv: "floordiv",
+    ast.Mod: "mod",
+    ast.Lt: "lt",
+    ast.Gt: "gt",
+    ast.GtE: "ge",
+    ast.LtE: "le",
+    ast.LShift: "lshift",
+    ast.RShift: "rshift",
+    ast.BitXor: "xor",
+    ast.BitOr: "or",
+    ast.BitAnd: "and",
+    ast.USub: "neg",
+    ast.UAdd: "pos",
+    ast.Invert: "invert",
+}
+
+class ScoperExprVisitor(ScoperVisitor):
+    def visit(self, node) -> BaseType:
+        if existing := getattr(node, "type", None):
+            return existing
+        res = super().visit(node)
+        if not res:
+            raise NotImplementedError(f"`{ast.unparse(node)}` {type(node)}")
+        res = res.resolve()
+        node.type = res
+        return res
+
+    def visit_Tuple(self, node: ast.Tuple) -> BaseType:
+        return TupleType([self.visit(e) for e in node.elts])
+
+    def visit_Constant(self, node: ast.Constant) -> BaseType:
+        if isinstance(node.value, str):
+            return TY_STR
+        elif isinstance(node.value, bool):
+            return TY_BOOL
+        elif isinstance(node.value, int):
+            return TY_INT
+        elif isinstance(node.value, complex):
+            return TY_COMPLEX
+        elif node.value is None:
+            return TY_NONE
+        else:
+            raise NotImplementedError(node, type(node))
+
+    def visit_Name(self, node: ast.Name) -> BaseType:
+        obj = self.scope.get(node.id)
+        if not obj:
+            raise NameError(f"Name {node.id} is not defined")
+        return obj.type
+
+    def visit_Compare(self, node: ast.Compare) -> BaseType:
+        # todo:
+        self.visit(node.left)
+        for op, right in zip(node.ops, node.comparators):
+            self.visit(right)
+        return TY_BOOL
+        #raise NotImplementedError(node)
+
+    def visit_Call(self, node: ast.Call) -> BaseType:
+        ftype = self.visit(node.func)
+        return self.visit_function_call(ftype, [self.visit(arg) for arg in node.args])
+
+    def visit_function_call(self, ftype: BaseType, arguments: List[BaseType]):
+        if not isinstance(ftype, FunctionType):
+            raise IncompatibleTypesError(f"Cannot call {ftype}")
+        #is_generic = any(isinstance(arg, TypeVariable) for arg in ftype.to_list())
+        equivalent = FunctionType(arguments, ftype.return_type)
+        try:
+            ftype.unify(equivalent)
+        except:
+            raise IncompatibleTypesError(f"Cannot call {ftype} with {equivalent}")
+        return ftype.return_type
+
+    def visit_Lambda(self, node: ast.Lambda) -> BaseType:
+        argtypes = [TypeVariable() for _ in node.args.args]
+        rtype = TypeVariable()
+        ftype = FunctionType(argtypes, rtype)
+        scope = self.scope.child(ScopeKind.FUNCTION)
+        scope.obj_type = ftype
+        scope.function = scope
+        node.scope = scope
+        for arg, ty in zip(node.args.args, argtypes):
+            scope.vars[arg.arg] = VarDecl(VarKind.LOCAL, ty)
+        decls = {}
+        visitor = ScoperExprVisitor(scope, decls)
+        rtype.unify(visitor.visit(node.body))
+        node.body.decls = decls
+        return ftype
+
+    def visit_BinOp(self, node: ast.BinOp) -> BaseType:
+        left, right = map(self.visit, (node.left, node.right))
+        try:
+            return self.visit_function_call(
+                self.visit_getattr(TypeType(left), f"__{DUNDER[type(node.op)]}__"),
+                [left, right]
+            )
+        except IncompatibleTypesError as e:
+            raise IncompatibleTypesError(f"{e} in `{ast.unparse(node)}`")
+
+    def visit_Attribute(self, node: ast.Attribute) -> BaseType:
+        ltype = self.visit(node.value)
+        try:
+            return self.visit_getattr(ltype, node.attr)
+        except IncompatibleTypesError as e:
+            raise IncompatibleTypesError(f"{e} in `{ast.unparse(node)}`")
+
+    def visit_getattr(self, ltype: BaseType, name: str):
+        bound = True
+        if isinstance(ltype, TypeType):
+            ltype = ltype.type_object
+            bound = False
+        if attr := ltype.members.get(name):
+            return attr
+        if meth := ltype.methods.get(name):
+            if bound:
+                return FunctionType(meth.parameters[1:], meth.return_type)
+            else:
+                return meth
+        raise IncompatibleTypesError(f"Type {ltype} has no attribute {name}")
+
+    def visit_List(self, node: ast.List) -> BaseType:
+        if not node.elts:
+            return PyList(TypeVariable())
+        elems = [self.visit(e) for e in node.elts]
+        if len(set(elems)) != 1:
+            raise NotImplementedError("List with different types not handled yet")
+        return PyList(elems[0])
+
+    def visit_Set(self, node: ast.Set) -> BaseType:
+        if not node.elts:
+            return PySet(TypeVariable())
+        elems = [self.visit(e) for e in node.elts]
+        if len(set(elems)) != 1:
+            raise NotImplementedError("Set with different types not handled yet")
+        return PySet(elems[0])
+
+    def visit_Dict(self, node: ast.Dict) -> BaseType:
+        if not node.keys:
+            return PyDict(TypeVariable())
+        keys = [self.visit(e) for e in node.keys]
+        values = [self.visit(e) for e in node.values]
+        if len(set(keys)) != 1 or len(set(values)) != 1:
+            raise NotImplementedError("Dict with different types not handled yet")
+        return PyDict(keys[0], values[0])
+
+    def visit_Subscript(self, node: ast.Subscript) -> BaseType:
+        raise NotImplementedError(node)
+
+    def visit_UnaryOp(self, node: ast.UnaryOp) -> BaseType:
+        raise NotImplementedError(node)
+
+    def visit_IfExp(self, node: ast.IfExp) -> BaseType:
+        self.visit(node.test)
+        then = self.visit(node.body)
+        else_ = self.visit(node.orelse)
+        if then != else_:
+            raise NotImplementedError("IfExp with different types not handled yet")
+        return then
+
+    def visit_Yield(self, node: ast.Yield) -> BaseType:
+        raise NotImplementedError(node)

trans/transpiler/phases/typing/scope.py

+from dataclasses import field, dataclass
+from enum import Enum
+from typing import Optional, Dict, List, Any
+
+from transpiler.phases.typing.types import BaseType
+
+
+class VarKind(Enum):
+    """Kind of variable."""
+    LOCAL = 1
+    """`xxx = ...`"""
+    GLOBAL = 2
+    """`global xxx"""
+    NONLOCAL = 3
+    """`nonlocal xxx`"""
+    SELF = 4
+    OUTER_DECL = 5
+
+
+class VarType:
+    pass
+
+
+class RuntimeValue:
+    pass
+
+
+@dataclass
+class VarDecl:
+    kind: VarKind
+    type: BaseType
+    val: Any = RuntimeValue()
+
+
+class ScopeKind(Enum):
+    GLOBAL = 1
+    """Global (module) scope"""
+    FUNCTION = 2
+    """Function scope"""
+    FUNCTION_INNER = 3
+    """Block (if, for, ...) scope inside a function"""
+    CLASS = 4
+    """Class scope"""
+
+
+@dataclass
+class Scope:
+    parent: Optional["Scope"] = None
+    kind: ScopeKind = ScopeKind.GLOBAL
+    function: Optional["Scope"] = None
+    global_scope: Optional["Scope"] = None
+    vars: Dict[str, VarDecl] = field(default_factory=dict)
+    children: List["Scope"] = field(default_factory=list)
+    obj_type: Optional[BaseType] = None
+
+    @staticmethod
+    def make_global():
+        res = Scope()
+        res.global_scope = res
+        return res
+
+    def child(self, kind: ScopeKind):
+        res = Scope(self, kind, self.function, self.global_scope)
+        self.children.append(res)
+        return res
+
+    def declare_local(self, name: str):
+        """Declares a local variable"""
+
+    def get(self, name: str) -> Optional[VarDecl]:
+        """
+        Gets the variable declaration of a variable in the current scope or any parent scope.
+        """
+        if (res := self.vars.get(name)) and res.kind == VarKind.LOCAL:
+            return res
+        if self.parent is not None:
+            return self.parent.get(name)
+        return None

trans/transpiler/phases/typing/stdlib.py

+import ast
+import dataclasses
+from dataclasses import dataclass, field
+from typing import Optional, List, Dict
+
+from transpiler.phases.typing.annotations import TypeAnnotationVisitor
+from transpiler.phases.typing.common import PRELUDE
+from transpiler.phases.typing.expr import ScoperExprVisitor
+from transpiler.phases.typing.scope import Scope, VarDecl, VarKind, ScopeKind
+from transpiler.phases.typing.types import BaseType, TypeOperator, FunctionType, TY_VARARG, TypeType, TypeVariable
+from transpiler.phases.utils import NodeVisitorSeq
+
+
+
+@dataclass
+class StdlibVisitor(NodeVisitorSeq):
+    scope: Scope = field(default_factory=lambda: PRELUDE)
+    cur_class: Optional[BaseType] = None
+    typevars: Dict[str, BaseType] = field(default_factory=dict)
+
+    def visit_Module(self, node: ast.Module):
+        for stmt in node.body:
+            self.visit(stmt)
+
+    def visit_Assign(self, node: ast.Assign):
+        self.scope.vars[node.targets[0].id] = VarDecl(VarKind.LOCAL, self.visit(node.value))
+
+    def visit_AnnAssign(self, node: ast.AnnAssign):
+        self.scope.vars[node.target.id] = VarDecl(VarKind.LOCAL, self.anno().visit(node.annotation))
+
+    def visit_ImportFrom(self, node: ast.ImportFrom):
+        pass
+
+    def visit_Import(self, node: ast.Import):
+        pass
+
+    def visit_ClassDef(self, node: ast.ClassDef):
+        typevars = []
+        for b in node.bases:
+            if isinstance(b, ast.Subscript) and isinstance(b.value, ast.Name) and b.value.id == "Generic":
+                if isinstance(b.slice, ast.Index):
+                    typevars = [b.slice.value.id]
+                elif isinstance(b.slice, ast.Tuple):
+                    typevars = [n.id for n in b.slice.value.elts]
+        if existing := self.scope.get(node.name):
+            ty = existing.type
+        else:
+            ty = TypeOperator([], node.name)
+            self.scope.vars[node.name] = VarDecl(VarKind.LOCAL, ty)
+        cl_scope = self.scope.child(ScopeKind.CLASS)
+        visitor = StdlibVisitor(cl_scope, ty)
+        for var in typevars:
+            visitor.typevars[var] = TypeType(TypeVariable(var))
+        for stmt in node.body:
+            visitor.visit(stmt)
+
+    def visit_FunctionDef(self, node: ast.FunctionDef):
+        arg_visitor = TypeAnnotationVisitor(self.scope.child(ScopeKind.FUNCTION), self.cur_class)
+        arg_types = [arg_visitor.visit(arg.annotation or arg.arg) for arg in node.args.args]
+        ret_type = arg_visitor.visit(node.returns)
+        ty = FunctionType(arg_types, ret_type)
+        if node.args.vararg:
+            ty.variadic = True
+            #arg_types.append(TY_VARARG)
+        if self.cur_class:
+            if isinstance(self.cur_class, TypeType):
+                #     ty_inst = FunctionType(arg_types[1:], ret_type)
+                #     self.cur_class.args[0].add_inst_member(node.name, ty_inst)
+                self.cur_class.type_object.methods[node.name] = ty.gen_sub(self.cur_class.type_object, self.typevars)
+            else:
+                self.cur_class.gen_methods[node.name] = lambda t: ty.gen_sub(t, self.typevars)
+        self.scope.vars[node.name] = VarDecl(VarKind.LOCAL, ty)
+
+    def visit_Assert(self, node: ast.Assert):
+        print("Type of", ast.unparse(node.test), ":=", ScoperExprVisitor().visit(node.test))
+
+    def visit_Call(self, node: ast.Call) -> BaseType:
+        ty_op = self.visit(node.func)
+        if isinstance(ty_op, type):
+            return ty_op(*[ast.literal_eval(arg) for arg in node.args])
+        raise NotImplementedError
+
+    def anno(self) -> "TypeAnnotationVisitor":
+        return TypeAnnotationVisitor(self.scope, self.cur_class)
+
+    def visit_str(self, node: str) -> BaseType:
+        if existing := self.scope.get(node):
+            return existing.type
+        raise NameError(node)
+
+    def visit_Name(self, node: ast.Name) -> BaseType:
+        return self.visit_str(node.id)
\ No newline at end of file

trans/transpiler/phases/typing/types.py

+from abc import ABC, abstractmethod
+from dataclasses import dataclass, field
+from typing import Dict, Optional, List, ClassVar, Callable
+
+
+class IncompatibleTypesError(Exception):
+    pass
+
+
+@dataclass
+class BaseType(ABC):
+    members: Dict[str, "BaseType"] = field(default_factory=dict, init=False)
+    methods: Dict[str, "FunctionType"] = field(default_factory=dict, init=False)
+
+    def resolve(self) -> "BaseType":
+        return self
+
+    @abstractmethod
+    def unify_internal(self, other: "BaseType"):
+        pass
+
+    def unify(self, other: "BaseType"):
+        a, b = self.resolve(), other.resolve()
+        if isinstance(b, TypeVariable):
+            a, b = b, a
+        a.unify_internal(b)
+
+    def contains(self, other: "BaseType") -> bool:
+        needle, haystack = other.resolve(), self.resolve()
+        return (needle is haystack) or haystack.contains_internal(needle)
+
+    @abstractmethod
+    def contains_internal(self, other: "BaseType") -> bool:
+        pass
+
+    def gen_sub(self, this: "BaseType", typevars) -> "Self":
+        return self
+
+    def __repr__(self):
+        return str(self)
+
+    def to_list(self) -> List["BaseType"]:
+        return [self]
+
+
+cur_var = 0
+
+
+@dataclass
+class TypeVariable(BaseType):
+    name: str = field(default_factory=lambda: chr(ord('a') + cur_var))
+    resolved: Optional[BaseType] = None
+
+    def __str__(self):
+        if self.resolved is None:
+            return self.name
+        return str(self.resolved)
+
+    def resolve(self) -> BaseType:
+        if self.resolved is None:
+            return self
+        return self.resolved.resolve()
+
+    def unify_internal(self, other: BaseType):
+        if self is not other:
+            if other.contains(self):
+                raise ValueError(f"Recursive type: {self} and {other}")
+            self.resolved = other
+
+    def contains_internal(self, other: BaseType) -> bool:
+        return self is other
+
+    def gen_sub(self, this: "BaseType", typevars) -> "Self":
+        if match := typevars.get(self.name):
+            return match
+        return self
+
+GenMethodFactory = Callable[["BaseType"], "FunctionType"]
+
+@dataclass
+class TypeOperator(BaseType, ABC):
+    args: List[BaseType]
+    name: str = None
+    variadic: bool = False
+    gen_methods: ClassVar[Dict[str, GenMethodFactory]] = {}
+
+    def __post_init__(self):
+        if self.name is None:
+            self.name = self.__class__.__name__
+        for name, factory in self.gen_methods.items():
+            self.methods[name] = factory(self)
+
+    def unify_internal(self, other: BaseType):
+        if not isinstance(other, TypeOperator):
+            raise IncompatibleTypesError()
+        if len(self.args) != len(other.args) and not (self.variadic or other.variadic):
+            raise IncompatibleTypesError(f"Cannot unify {self} and {other} with different number of arguments")
+        for a, b in zip(self.args, other.args):
+            a.unify(b)
+
+    def contains_internal(self, other: "BaseType") -> bool:
+        return any(arg.contains(other) for arg in self.args)
+
+    def __str__(self):
+        return self.name + (f"<{', '.join(map(str, self.args))}>" if self.args else "")
+
+    def __hash__(self):
+        return hash((self.name, tuple(self.args)))
+
+    def gen_sub(self, this: BaseType, typevars) -> "Self":
+        res = object.__new__(self.__class__)
+        if isinstance(this, TypeOperator):
+            vardict = dict(zip(typevars.keys(), this.args))
+        else:
+            vardict = {}
+        res.args = [arg.resolve().gen_sub(this, vardict) for arg in self.args]
+        res.name = self.name
+        res.variadic = self.variadic
+        return res
+
+    def to_list(self) -> List["BaseType"]:
+        return [self, *self.args]
+
+
+class FunctionType(TypeOperator):
+    def __init__(self, args: List[BaseType], ret: BaseType):
+        super().__init__([ret, *args])
+
+    @property
+    def parameters(self):
+        return self.args[1:]
+
+    @property
+    def return_type(self):
+        return self.args[0]
+
+    def __str__(self):
+        ret, *args = map(str, self.args)
+        if self.variadic:
+            args.append(f"*args")
+        if args:
+            args = f"({', '.join(args)})"
+        else:
+            args = "()"
+        return f"{args} -> {ret}"
+
+class CppType(TypeOperator):
+    def __init__(self, name: str):
+        super().__init__([name], name)
+
+    def __str__(self):
+        return self.name
+
+class Union(TypeOperator):
+    def __init__(self, left: BaseType, right: BaseType):
+        super().__init__([left, right], "Union")
+
+class TypeType(TypeOperator):
+    def __init__(self, arg: BaseType):
+        super().__init__([arg], "Type")
+
+    @property
+    def type_object(self) -> BaseType:
+        return self.args[0]
+
+
+TY_TYPE = TypeOperator([], "type")
+TY_INT = TypeOperator([], "int")
+TY_STR = TypeOperator([], "str")
+TY_BOOL = TypeOperator([], "bool")
+TY_COMPLEX = TypeOperator([], "complex")
+TY_NONE = TypeOperator([], "NoneType")
+TY_MODULE = TypeOperator([], "module")
+TY_VARARG = TypeOperator([], "vararg")
+TY_SELF = TypeOperator([], "Self")
+TY_SELF.gen_sub = lambda this, typevars: this
+
+class PyList(TypeOperator):
+    def __init__(self, arg: BaseType):
+        super().__init__([arg], "list")
+
+    @property
+    def element_type(self):
+        return self.args[0]
+
+class PySet(TypeOperator):
+    def __init__(self, arg: BaseType):
+        super().__init__([arg], "set")
+
+    @property
+    def element_type(self):
+        return self.args[0]
+
+class PyDict(TypeOperator):
+    def __init__(self, key: BaseType, value: BaseType):
+        super().__init__([key, value], "dict")
+
+    @property
+    def key_type(self):
+        return self.args[0]
+
+    @property
+    def value_type(self):
+        return self.args[1]
+
+class TupleType(TypeOperator):
+    def __init__(self, args: List[BaseType]):
+        super().__init__(args, "tuple")
+
+class ForkResult(TypeOperator):
+    def __init__(self, args: BaseType):
+        super().__init__([args], "ForkResult")
+
+    @property
+    def return_type(self):
+        return self.args[0]

trans/transpiler/phases/utils.py

+from transpiler.utils import UnsupportedNodeError
+
+
+class NodeVisitorSeq:
+    def visit(self, node):
+        """Visit a node."""
+        if type(node) == list:
+            for n in node:
+                self.visit(n)
+        else:
+            for parent in node.__class__.__mro__:
+                if visitor := getattr(self, 'visit_' + parent.__name__, None):
+                    return visitor(node)
+            else:
+                self.missing_impl(node)
+
+    def missing_impl(self, node):
+        raise UnsupportedNodeError(node)

trans/transpiler/scope.py

-# coding: utf-8
-import ast
-from dataclasses import dataclass, field
-from enum import Enum
-from typing import Optional, Dict, Tuple
-
-
-class VarKind(Enum):
-    """Kind of variable."""
-    LOCAL = 1
-    GLOBAL = 2
-    NONLOCAL = 3
-    SELF = 4
-
-
-@dataclass
-class VarDecl:
-    kind: VarKind
-    val: Optional[Tuple[str, ast.AST]]
-    future: bool = False
-
-
-@dataclass
-class Scope:
-    parent: Optional["Scope"] = None
-    is_function: bool = False
-    vars: Dict[str, VarDecl] = field(default_factory=dict)
-
-    def is_global(self) -> bool:
-        """
-        Determines whether this scope is the global scope. The global scope is the only scope to have no parent.
-        """
-        return self.parent is None
-
-    def exists(self, name: str) -> bool:
-        """
-        Determines whether a variable exists in the current scope or any parent scope.
-        """
-        return name in self.vars or (self.parent is not None and self.parent.exists(name))
-
-    def get(self, name: str) -> Optional[VarDecl]:
-        """
-        Gets the variable declaration of a variable in the current scope or any parent scope.
-        """
-        if res := self.vars.get(name):
-            return res
-        if self.parent is not None:
-            return self.parent.get(name)
-        return None
-
-    def exists_local(self, name: str) -> bool:
-        """
-        Determines whether a variable exists in the current function or global scope.
-        The check does not cross function boundaries; i.e. global variables are not taken into account from inside
-        functions.
-        """
-        return name in self.vars or (
-                not self.is_function and self.parent is not None and self.parent.exists_local(name))
-
-    def child(self) -> "Scope":
-        """
-        Creates a child scope with a new variable dictionary.
-        This is used for first-level elements of a function.
-        """
-        return Scope(self, False, {})
-
-    def child_share(self) -> "Scope":
-        """
-        Creates a child scope sharing the variable dictionary with the parent scope.
-        This is used for Python blocks, which share the variable scope with their parent block.
-        """
-        return Scope(self, False, self.vars)
-
-    def function(self, **kwargs) -> "Scope":
-        """
-        Creates a function scope.
-        """
-        return Scope(self, True, **kwargs)
-
-    def is_root(self) -> Optional[Dict[str, VarDecl]]:
-        """
-        Determines whether this scope is a root scope.
-
-        A root scope is either the global scope, or the first inner scope of a function.
-        Variable declarations in the generated code only ever appear in root scopes.
-        :return: `None` if this scope is not a root scope, otherwise the variable dictionary of the root scope.
-        """
-        if self.parent is None:
-            return self.vars
-        if self.parent.is_function:
-            return self.parent.vars
-        return None
-
-    def declare(self, name: str, val: Optional[Tuple[str, ast.AST]] = None, future: bool = False) -> Optional[str]:
-        if self.exists_local(name):
-            # If the variable already exists in the current function or global scope, we don't need to declare it again.
-            # This is simply an assignment.
-            return None
-        vdict, prefix = self.vars, ""
-        if (root_vars := self.is_root()) is not None:
-            vdict, prefix = root_vars, "auto "  # Root scope declarations can use `auto`.
-        vdict[name] = VarDecl(VarKind.LOCAL, val, future)
-        return prefix

trans/transpiler/utils.py

+# coding: utf-8
+import ast
+from dataclasses import dataclass
+from itertools import zip_longest
+from typing import Union
+
+
+def compare_ast(node1: Union[ast.expr, list[ast.expr]], node2: Union[ast.expr, list[ast.expr]]) -> bool:
+    if type(node1) is not type(node2):
+        return False
+
+    if isinstance(node1, ast.AST):
+        for k, v in vars(node1).items():
+            if k in {"lineno", "end_lineno", "col_offset", "end_col_offset", "ctx", "type"}:
+                continue
+            if not compare_ast(v, getattr(node2, k)):
+                return False
+        return True
+
+    elif isinstance(node1, list) and isinstance(node2, list):
+        return all(compare_ast(n1, n2) for n1, n2 in zip_longest(node1, node2))
+    else:
+        return node1 == node2
+
+
+@dataclass
+class UnsupportedNodeError(Exception):
+    node: ast.AST
+
+    def __str__(self) -> str:
+        return f"Unsupported node: {self.node.__class__.__mro__} {ast.dump(self.node)}"