Make __() optional for standard constructors (#7)

fixes #6

* [late] allow omitting `__()` for basic constructors
* [readme] mention Optional[]
* [late] fix list of immutable types
* [latebinding] wrap structured types because members may be mutable

README.md

@@ -1,18 +1,18 @@
 [
-    ![lincense](https://img.shields.io/github/license/neogeny/Late)
+    ![license](https://img.shields.io/github/license/neogeny/Late)
 ](https://www.gnu.org/licenses/lgpl-3.0.html)
 [
     ![version](https://img.shields.io/pypi/pyversions/late.svg)
 ](https://www.python.org/downloads/)
 [
     ![fury](https://badge.fury.io/py/Late.svg)
 ](https://pypi.org/project/Late/)
-![downloada](https://img.shields.io/pypi/dm/Late.svg)
+![downloads](https://img.shields.io/pypi/dm/Late.svg)
 [
     ![tests](https://github.com/neogeny/late/actions/workflows/default.yml/badge.svg)
 ](https://github.com/neogeny/late/actions/workflows/default.yml)
 
-# 包 Late
+# 包 Late 1.3.0b1
 Late binding for Python default arguments
 
 
@@ -66,7 +66,13 @@ in a way so that type checkers do not complain about using ``None`` as the defau
 def f(x: list[Any] | None = None) -> list[Any]:
 ```
 
-Another problem with the above declaration is that calling ``f(None)`` passes type checking, 
+or:
+
+```python
+def f(x: Optional[list[Any]] = None) -> list[Any]:
+```
+
+Another problem with the above declarations is that calling ``f(None)`` passes type checking, 
 when that's probably not the preferred situation.
 
 
@@ -90,10 +96,16 @@ assert f() == [1]
 
 ```
 
+For constructors for basic structured types, the ``__()`` call may be omitted:
+
+```python
+@latebinding
+def f(x: list[Any] = []) -> list[Any]:
+```
 
 ### Working with classes
 
-**包 Late** also works with classes and `dataclass`. The ``@latebinding`` decorator 
+**包 Late** also works with classes and ``dataclass``. The ``@latebinding`` decorator 
 must be the outer one:
 
 ```python

late/__init__.py

@@ -4,7 +4,7 @@
 from collections.abc import Callable, Iterator
 from typing import Any, NamedTuple, TypeVar
 
-__all__ = ['latebinding', 'late', '__']
+__all__ = ['latebinding']
 
 
 _R = TypeVar('_R')
@@ -17,7 +17,7 @@ class _LateBound(NamedTuple):
 
 
 def late(o: _T | Iterator[_V] | Callable[[], _R]) -> _T | _V | _R:
-    if isinstance(o, int | float | str | bytes | bool | tuple | bytearray | frozenset):
+    if isinstance(o, int | float | bool | str | bytes):
         return o  # type: ignore
 
     return _LateBound(actual=o)  # type: ignore
@@ -27,19 +27,24 @@ def late(o: _T | Iterator[_V] | Callable[[], _R]) -> _T | _V | _R:
 包 = late
 
 
-def _lateargs(func: Callable, **kwargs) -> dict[str, Any]:
+def _resolve_value(value):
+    if isinstance(value, _LateBound):
+        value = value.actual
+    if isinstance(value, int | float | bool | str | bytes):
+        return value
+    if isinstance(value, Iterator):
+        return next(value)
+    if inspect.isfunction(value):
+        return value()
+    return copy.deepcopy(value)
+
 
-    def resolve_default(value):
-        if isinstance(value, Iterator):
-            return next(value)
-        if inspect.isfunction(value):
-            return value()
-        return copy.deepcopy(value)
+def _lateargs(func: Callable, **kwargs) -> dict[str, Any]:
 
     lateargs = {
-        name: resolve_default(param.default.actual)
+        name: _resolve_value(param.default)
         for name, param in inspect.signature(func).parameters.items()
-        if name not in kwargs and isinstance(param.default, _LateBound)
+        if name not in kwargs and param.default != inspect._empty
     }
     return {**kwargs, **lateargs}
 

late/_version.py

@@ -1 +1 @@
-__version__ = '1.3.0b1'
+__version__ = '1.2.1'

ruff.toml

@@ -10,7 +10,7 @@ select = [
     # 'ERA', # commented out code
 ]
 ignore = [
-    'B008',
+    'B006', 'B008',
     'E501', 'E741', 'E402',
     'S101', 'S102', 'S105', 'S301', 'S311',
     'C408',
@@ -23,7 +23,7 @@ ignore = [
     'PLR0913', 'PLR2004', 'PLR0904', 'PLR0915',
     'PLW0603', 'PLW2901', 'PLW3201',
     'RET505',
-    'RUF009',
+    'RUF008', 'RUF009',
 ]
 exclude = []
 

test/complex_test.py

@@ -5,7 +5,7 @@
 
 def test_recursion():
     @latebinding
-    def f(x: list[list[Any]] = __([[]])) -> list[list[Any]]:
+    def f(x: list[list[Any]] = [[]]) -> list[list[Any]]:
         x[0].append(1)
         return x
 

test/simple_test.py

@@ -1,13 +1,13 @@
 import inspect
 from typing import Any
 
-from late import __, _LateBound, latebinding, 包
+from late import latebinding, 包
 
 
 def test_with_list():
 
     @latebinding
-    def f(x: list[Any] = __([])) -> list[Any]:
+    def f(x: list[Any] = []) -> list[Any]:
         x.append(1)
         return x
 
@@ -18,13 +18,13 @@ def f(x: list[Any] = __([])) -> list[Any]:
 
 def test_immutable():
     @latebinding
-    def f(x: frozenset[Any] = __(frozenset()), y: set = __(set())):
+    def f(x: frozenset[Any] = frozenset(), y: set = set()):
         return
 
     param = inspect.signature(f).parameters['x']
     assert type(param.default) is frozenset
     param = inspect.signature(f).parameters['y']
-    assert type(param.default) is _LateBound
+    assert type(param.default) is set
 
 
 def test_kanji():