# ADR-0003 - Avoid introducing Groovy types to public API

## Status

- ACCEPTED on 2024-01-12

## Context

Gradle's public API requires equal access from all JVM-based languages.
Kotlin, Groovy, Java, and other JVM-based languages should be able to use the Gradle API without relying on another language's standard library.

Historically, Gradle has shipped with some Groovy types in very prominent APIs.

  }

  private static Type[] toArray(Collection<Type> types) {
    return types.toArray(new Type[0]);
  }

  private static Iterable<Type> filterUpperBounds(Iterable<Type> bounds) {
    return Iterables.filter(bounds, Predicates.not(Predicates.<Type>equalTo(Object.class)));
  }

  private static void disallowPrimitiveType(Type[] types, String usedAs) {
    for (Type type : types) {
      if (type instanceof Class) {

package loggertypes

// TargetType indicates type of the target e.g. console, http, kafka
type TargetType uint8

//go:generate stringer -type=TargetType -trimprefix=Target $GOFILE

// Constants for target types
const (
	_ TargetType = iota
	TargetConsole
	TargetHTTP
	TargetKafka
)

// TargetStats contains statistics for a target.
type TargetStats struct {

import types
from collections.abc import Callable
from enum import Enum
from typing import Any, TypeVar, Union

from pydantic import BaseModel
from pydantic.main import IncEx as IncEx

DecoratedCallable = TypeVar("DecoratedCallable", bound=Callable[..., Any])
UnionType = getattr(types, "UnionType", Union)
ModelNameMap = dict[type[BaseModel] | type[Enum], str]

    print(data)
```

### Generic types { #generic-types }

Some types can take "type parameters" in square brackets, to define their internal types, for example a "list of strings" would be declared `list[str]`.

These types that can take type parameters are called **Generic types** or **Generics**.

You can use the same builtin types as generics (with square brackets and types inside):

* `list`
* `tuple`
* `set`

在同樣的地方，你按 `Ctrl+Space` 嘗試自動完成，然後你會看到：

<img src="/img/python-types/image02.png">

有了這些，你可以往下捲動查看選項，直到找到一個「看起來眼熟」的：

<img src="/img/python-types/image03.png">

## 更多動機 { #more-motivation }

看這個函式，它已經有型別提示了：

{* ../../docs_src/python_types/tutorial003_py310.py hl[1] *}

因為編輯器知道變數的型別，你不只會得到自動完成，還會得到錯誤檢查：

<img src="/img/python-types/image04.png">

現在你知道要修正它，把 `age` 用 `str(age)` 轉成字串：

~~ KIND, either express or implied.  See the License for the
~~ specific language governing permissions and limitations
~~ under the License.

 ---
 Default Dependency Types
 ---
 Hervé Boutemy
 ---
 2024-04-02
 ---

Default Dependency Types Reference

  Defined in <<<DefaultTypeProvider>>>
  ({{{./apidocs/org/apache/maven/repository/internal/type/DefaultTypeProvider.html}javadoc}},

在同样的位置，你用 `Ctrl+Space` 触发自动补全，就能看到：

<img src="/img/python-types/image02.png">

这样，你可以滚动查看选项，直到找到那个“看着眼熟”的：

<img src="/img/python-types/image03.png">

## 更多动机 { #more-motivation }

看这个已经带有类型提示的函数：

{* ../../docs_src/python_types/tutorial003_py310.py hl[1] *}

因为编辑器知道变量的类型，你不仅能得到补全，还能获得错误检查：

<img src="/img/python-types/image04.png">

现在你知道需要修复它，用 `str(age)` 把 `age` 转成字符串：

<img src="/img/python-types/image02.png">

これであれば、あなたは「ベルを鳴らす」ものを見つけるまで、オプションを見てスクロールできます:

<img src="/img/python-types/image03.png">

## より強い動機 { #more-motivation }

この関数を見てください。すでに型ヒントを持っています:

{* ../../docs_src/python_types/tutorial003_py310.py hl[1] *}

エディタは変数の型を知っているので、補完だけでなく、エラーチェックをすることもできます:

<img src="/img/python-types/image04.png">

# Advanced Python Types { #advanced-python-types }

Here are some additional ideas that might be useful when working with Python types.

## Using `Union` or `Optional` { #using-union-or-optional }

If your code for some reason can't use `|`, for example if it's not in a type annotation but in something like `response_model=`, instead of using the vertical bar (`|`) you can use `Union` from `typing`.