deps: drop py3.8, support py3.9+

.github/workflows/ci.yml

@@ -16,9 +16,6 @@ jobs:
       fail-fast: false
       matrix:
         value:
-          - name: "3.8"
-            python-version: "3.8"
-            extra-install: ""
           - name: "3.9"
             python-version: "3.9"
             extra-install: ""
@@ -28,15 +25,18 @@ jobs:
           - name: "3.11"
             python-version: "3.11"
             extra-install: ""
-          - name: "3.11-pre-beartype"
-            python-version: "3.11"
-            extra-install: "pip install --upgrade --pre beartype"
           - name: "3.12"
             python-version: "3.12"
             extra-install: ""
           - name: "3.12-pre-beartype"
             python-version: "3.12"
             extra-install: "pip install --upgrade --pre beartype"
+          - name: "3.13"
+            python-version: "3.13"
+            extra-install: ""
+          - name: "3.13-pre-beartype"
+            python-version: "3.13"
+            extra-install: "pip install --upgrade --pre beartype"
 
     name: Test ${{ matrix.value.name }}
     steps:

.readthedocs.yaml

@@ -3,7 +3,7 @@ version: 2
 build:
   os: ubuntu-22.04
   tools:
-    python: "3.11"
+    python: "3.12"
   jobs:
     pre_build:
       # Generate the Sphinx configuration for this Jupyter Book, so it builds.

README.md

@@ -17,7 +17,7 @@ If you notice any issues with the new release, please open an issue.
 
 # Installation
 
-Plum requires Python 3.8 or higher.
+Plum requires Python 3.9 or higher.
 
 ```bash
 pip install plum-dispatch

benchmark.py

@@ -1,5 +1,3 @@
-from typing import Tuple
-
 import numpy as np
 from tests.util import benchmark
 
@@ -35,12 +33,12 @@ def f2(x):
 
 
 @dispatch
-def g2(x: Tuple[int]):
+def g2(x: tuple[int]):
     pass
 
 
 @dispatch
-def g2(x: Tuple[str]):
+def g2(x: tuple[str]):
     pass
 
 

check_linter_assertions.py

@@ -2,15 +2,15 @@
 import subprocess
 import sys
 from collections import defaultdict
+from collections.abc import Callable
 from pathlib import Path
-from typing import Callable, Dict, List, Tuple
 
-FileLineInfo = Dict[Path, Dict[int, List[str]]]
+FileLineInfo = dict[Path, dict[int, list[str]]]
 """type: Type of a nested dictionary that gives for a collection of files line-wise
 information, where the information is of the form `list[str]`."""
 
 
-def next_noncomment_line(index: int, lines: List[str], path: Path) -> int:
+def next_noncomment_line(index: int, lines: list[str], path: Path) -> int:
     """Starting at `index`, find the next line with code.
 
     Args:
@@ -70,7 +70,7 @@ def parse_assertions(source_dir: Path, linter: str) -> FileLineInfo:
     return asserted_errors
 
 
-def parse_mypy_line(line: str) -> Tuple[Path, int, str, str]:
+def parse_mypy_line(line: str) -> tuple[Path, int, str, str]:
     """Parse a line of the output of `mypy`.
 
     Args:
@@ -90,7 +90,7 @@ def parse_mypy_line(line: str) -> Tuple[Path, int, str, str]:
     return Path(path).resolve(), int(line_number), status, message
 
 
-def parse_pyright_line(line: str) -> Tuple[Path, int, str, str]:
+def parse_pyright_line(line: str) -> tuple[Path, int, str, str]:
     """Parse a line of the output of `pyright`.
 
     Args:
@@ -112,7 +112,7 @@ def parse_pyright_line(line: str) -> Tuple[Path, int, str, str]:
     return Path(path.strip()).resolve(), int(line_number), status, message
 
 
-parse_line: Dict[str, Callable[[str], Tuple[Path, int, str, str]]] = {
+parse_line: dict[str, Callable[[str], tuple[Path, int, str, str]]] = {
     "mypy": parse_mypy_line,
     "pyright": parse_pyright_line,
 }

docs/types.md

@@ -8,7 +8,7 @@ that all types and type hints supported by Beartype are also supported by Plum.
 Here are a few examples:
 
 ```python
-from typing import Union, Optional, List, Dict
+from typing import Union, Optional
 
 from plum import dispatch
 
@@ -34,7 +34,7 @@ def f(x: list) -> str:
 
 
 @dispatch
-def f(x: List[int]) -> str:
+def f(x: list[int]) -> str:
     return "list of int"
 
 
@@ -44,11 +44,11 @@ def f(x: Optional[dict]) -> Optional[str]:
 
 
 @dispatch
-def f(x: Dict[int, str]) -> str:
+def f(x: dict[int, str]) -> str:
    return "dict of int to str"
 ```
 
-Although parametric types such as `List[int]` and `Dict[int, str]` are fully
+Although parametric types such as `list[int]` and `dict[int, str]` are fully
 supported, they do incur a performance penalty.
 For optimal performance, is recommended to use parametric types only where necessary.
 `Union` and `Optional` do not incur a performance penalty.
@@ -85,7 +85,7 @@ Plum already opts into this behaviour and will use it once it becomes available.
 
 The type system is *covariant*, as opposed to Julia's type
 system, which is *invariant*.
-For example, this means that `List[T1]` is a subtype of `List[T2]` whenever
+For example, this means that `list[T1]` is a subtype of `list[T2]` whenever
 `T1` is a subtype of `T2`.
 
 ## Performance and Faithful Types

plum/__init__.py

@@ -1,8 +1,10 @@
-# Plum previously exported a number of types. As of recently, the user can use the
-# versions from `typing`. To not break backward compatibility, we still export these
-# types.
+# Plum previously exported a number of types. As of recently, the user can use
+# the versions from `typing`. To not break backward compatibility, we still
+# export these types.
+from typing import Dict, List, Tuple, Union  # noqa: F401, UP035
+
+# isort: split
 from functools import partial
-from typing import Dict, List, Tuple, Union  # noqa: F401
 
 from beartype import (
     BeartypeConf as _BeartypeConf,

plum/alias.py

@@ -27,9 +27,7 @@
 """
 
 from functools import wraps
-from typing import List, TypeVar, Union, _type_repr
-
-from .typing import get_args
+from typing import TypeVar, Union, _type_repr, get_args
 
 __all__ = ["activate_union_aliases", "deactivate_union_aliases", "set_union_alias"]
 
@@ -141,7 +139,7 @@ def deactivate_union_aliases() -> None:
     _union_type.__str__ = _original_str
 
 
-_ALIASED_UNIONS: List = []
+_ALIASED_UNIONS: list = []
 
 
 def set_union_alias(union: UnionT, alias: str) -> UnionT:

plum/dispatcher.py

@@ -1,7 +1,7 @@
 import sys
 from dataclasses import dataclass, field
 from functools import partial
-from typing import Any, Dict, Optional, Tuple, TypeVar, Union, overload
+from typing import Any, Optional, TypeVar, Union, overload
 
 from .function import Function
 from .overload import get_overloads
@@ -13,8 +13,8 @@
 T = TypeVar("T", bound=Callable[..., Any])
 
 
-_dataclass_kw_args: Dict[str, Any] = {}
-if sys.version_info >= (3, 10):  # pragma: specific no cover 3.8 3.9
+_dataclass_kw_args: dict[str, Any] = {}
+if sys.version_info >= (3, 10):  # pragma: specific no cover 3.9
     _dataclass_kw_args |= {"slots": True}
 
 
@@ -34,8 +34,8 @@ class Dispatcher:
     """
 
     warn_redefinition: bool = False
-    functions: Dict[str, Function] = field(default_factory=dict)
-    classes: Dict[str, Dict[str, Function]] = field(default_factory=dict)
+    functions: dict[str, Function] = field(default_factory=dict)
+    classes: dict[str, dict[str, Function]] = field(default_factory=dict)
 
     @overload
     def __call__(self, method: T, /, *, precedence: int = ...) -> T: ...
@@ -74,7 +74,7 @@ def __call__(
         return self._add_method(method, None, precedence=precedence)
 
     def multi(
-        self, *signatures: Union[Signature, Tuple[TypeHint, ...]]
+        self, *signatures: Union[Signature, tuple[TypeHint, ...]]
     ) -> Callable[[Callable], Function]:
         """Decorator to register multiple signatures at once.
 

plum/function.py

@@ -3,7 +3,7 @@
 from copy import copy
 from functools import wraps
 from types import MethodType
-from typing import Any, Callable, List, Optional, Protocol, Tuple, TypeVar, Union
+from typing import Any, Callable, Optional, Protocol, TypeVar, Union
 
 from .method import Method
 from .resolver import AmbiguousLookupError, NotFoundLookupError, Resolver
@@ -20,7 +20,7 @@
 # `typing.Self` is available for Python 3.11 and higher.
 try:  # pragma: specific no cover 3.11
     from typing import Self
-except ImportError:  # pragma: specific no cover 3.8 3.9 3.10
+except ImportError:  # pragma: specific no cover 3.10
     Self = TypeVar("Self", bound="Function")
 
 SomeExceptionType = TypeVar("SomeExceptionType", bound=Exception)
@@ -96,12 +96,12 @@ def __init__(
         self._warn_redefinition = warn_redefinition
 
         # Initialise pending and resolved methods.
-        self._pending: List[Tuple[Callable, Optional[Signature], int]] = []
+        self._pending: list[tuple[Callable, Optional[Signature], int]] = []
         self._resolver = Resolver(
             self.__name__,
             warn_redefinition=self._warn_redefinition,
         )
-        self._resolved: List[Tuple[Callable, Signature, int]] = []
+        self._resolved: list[tuple[Callable, Signature, int]] = []
 
     @property
     def owner(self):
@@ -125,7 +125,7 @@ def __doc__(self) -> Optional[str]:
         """
         try:
             self._resolve_pending_registrations()
-        except NameError:  # pragma: specific no cover 3.7 3.8 3.9
+        except NameError:  # pragma: specific no cover 3.9
             # When `staticmethod` is combined with
             # `from __future__ import annotations`, in Python 3.10 and higher
             # `staticmethod` will attempt to inherit `__doc__` (see
@@ -176,7 +176,7 @@ def __doc__(self, value: str) -> None:
         self._doc = value if value else ""
 
     @property
-    def methods(self) -> List[Signature]:
+    def methods(self) -> list[Signature]:
         """list[:class:`.signature.Signature`]: All available methods."""
         self._resolve_pending_registrations()
         return self._resolver.methods
@@ -199,7 +199,7 @@ def dispatch(
         return self
 
     def dispatch_multi(
-        self: Self, *signatures: Union[Signature, Tuple[TypeHint, ...]]
+        self: Self, *signatures: Union[Signature, tuple[TypeHint, ...]]
     ) -> Callable[[Callable], Self]:
         """Decorator to extend the function with multiple signatures at once.
 
@@ -296,8 +296,8 @@ def _resolve_pending_registrations(self) -> None:
             self.clear_cache(reregister=False)
 
     def resolve_method(
-        self, target: Union[Tuple[object, ...], Signature]
-    ) -> Tuple[Callable, TypeHint]:
+        self, target: Union[tuple[object, ...], Signature]
+    ) -> tuple[Callable, TypeHint]:
         """Find the method and return type for arguments.
 
         Args:
@@ -336,7 +336,7 @@ def resolve_method(
 
     def _handle_not_found_lookup_error(
         self, ex: NotFoundLookupError
-    ) -> Tuple[Callable, TypeHint]:
+    ) -> tuple[Callable, TypeHint]:
         if not self.owner:
             # Not in a class. Nothing we can do.
             raise ex from None
@@ -384,9 +384,9 @@ def __call__(self, *args, **kw_args):
 
     def _resolve_method_with_cache(
         self,
-        args: Union[Tuple[object, ...], Signature, None] = None,
-        types: Optional[Tuple[TypeHint, ...]] = None,
-    ) -> Tuple[Callable, TypeHint]:
+        args: Union[tuple[object, ...], Signature, None] = None,
+        types: Optional[tuple[TypeHint, ...]] = None,
+    ) -> tuple[Callable, TypeHint]:
         if args is None and types is None:
             raise ValueError(
                 "Arguments `args` and `types` cannot both be `None`. "
@@ -525,7 +525,7 @@ def wrapped_method(*args, **kw_args):
         return wrapped_method
 
     @property
-    def methods(self) -> List[Signature]:
+    def methods(self) -> list[Signature]:
         """list[:class:`.signature.Signature`]: All available methods."""
         return self._f.methods
 

plum/method.py

@@ -1,6 +1,7 @@
 import inspect
 import typing
-from typing import Callable, List, Optional, Set, Tuple
+from collections.abc import Callable
+from typing import Optional
 
 from rich.padding import Padding
 from rich.text import Text
@@ -96,7 +97,7 @@ def __rich_console__(self, console, options):
 
     def repr_mismatch(
         self,
-        mismatches: Set[int] = frozenset(),
+        mismatches: set[int] = frozenset(),
         varargs_matched: bool = True,
     ) -> str:
         """Version of `__repr__` that can print which arguments are mismatched. This
@@ -168,7 +169,7 @@ def __rich_console__(self, console, options):
             yield Padding(sum(method_repr, Text(f"[{i}] ")), (0, 4))
 
 
-def extract_arg_names(f: Callable) -> Tuple[List[str], List[str], Optional[str]]:
+def extract_arg_names(f: Callable) -> tuple[list[str], list[str], Optional[str]]:
     """Extract the argument names for a function.
 
     Args:

plum/overload.py

@@ -1,6 +1,6 @@
 import sys
 
-if sys.version_info >= (3, 11):  # pragma: specific no cover 3.7 3.8 3.9 3.10
+if sys.version_info >= (3, 11):  # pragma: specific no cover 3.9 3.10
     from typing import get_overloads, overload
 else:  # pragma: specific no cover 3.11
     from typing_extensions import get_overloads, overload

plum/parametric.py

@@ -1,5 +1,5 @@
 import contextlib
-from typing import Type, TypeVar, Union
+from typing import TypeVar, Union
 
 from typing_extensions import deprecated
 
@@ -472,7 +472,7 @@ def type_parameter(x):
     )
 
 
-def type_nonparametric(q: T) -> Type[T]:
+def type_nonparametric(q: T) -> type[T]:
     """Return the non-parametric type of an object.
 
     :mod:`plum.parametric` produces parametric subtypes of classes. This method
@@ -540,7 +540,7 @@ def type_nonparametric(q: T) -> Type[T]:
     )
 
 
-def type_unparametrized(q: T) -> Type[T]:
+def type_unparametrized(q: T) -> type[T]:
     """Return the unparametrized type of an object.
 
     :mod:`plum.parametric` produces parametric subtypes of classes.  This