from typing import Optional


def say_hi(name: Optional[str]):
    print(f"Hey {name}!")
```

參數 `name` 被標註為 `Optional[str]`，但它並不是可選的；你不能在沒有該參數的情況下呼叫這個函式：

```Python
say_hi()  # 糟了，這會拋出錯誤！😱
```

參數 `name` 仍是必填（不是可選），因為它沒有預設值。不過，`name` 可以接受 `None` 作為值：

```Python
say_hi(name=None)  # 這可行，None 是有效的 🎉
```

好消息是，多數情況下你可以直接用 `|` 來定義型別聯集：

```python
def say_hi(name: str | None):
    print(f"Hey {name}!")

	type City struct {
		gorm.Model
		Name string `gorm:"unique"`
	}

	db, err := OpenTestConnection(&gorm.Config{TranslateError: true})
	if err != nil {
		t.Fatalf("failed to connect database, got error %v", err)
	}

	dialectors := map[string]bool{"sqlite": true, "postgres": true, "gaussdb": true, "mysql": true, "sqlserver": true}
	if supported, found := dialectors[db.Dialector.Name()]; !(found && supported) {
		return
	}

    }

    /**
     * Updates crawling information parameters for the specified session.
     * Sets the name and expiration time based on the provided parameters.
     *
     * @param sessionId the session ID to update
     * @param name the name to set for the crawling session (uses system name if blank)
     * @param dayForCleanup number of days until cleanup (sets expiration if >= 0)

        public void setParameterValues(String name, String[] values) {
            parameters.put(name, values);
        }

        public void setParameter(String name, String value) {
            singleParameters.put(name, value);
        }

        @Override
        public String[] getParameterValues(String name) {
            return parameters.get(name);
        }

        @Override

name: Linters and Tests

on:
  pull_request:
    branches:
      - master

# This ensures that previous jobs for the PR are canceled when the PR is
# updated.
concurrency:
  group: ${{ github.workflow }}-${{ github.head_ref }}
  cancel-in-progress: true

permissions:
  contents: read

jobs:
  build:
    name: Go ${{ matrix.go-version }} on ${{ matrix.os }}
    runs-on: ${{ matrix.os }}
    strategy:
      matrix:

            } else {
                current.println('---')
                if (test.name != null && test.name.isBlank() == false) {
                    if(names.add(test.name) == false) {
                        throw new InvalidUserDataException("Duplicated snippet name '$test.name': $test")
                    }
                    current.println("\"$test.name\":")
                } else {

```python
from asyncer import asyncify
from fastapi import FastAPI

app = FastAPI()


def do_blocking_work(name: str) -> str:
    # Some blocking I/O operation
    return f"Hello {name}"


@app.get("/items/")
async def read_items():
    result = await asyncify(do_blocking_work)(name="World")
    return {"message": result}
```

And run async code inside of blocking sync code with `syncify()`:

```python

) {
    val gradleRootProject = when {
        project.name == "gradle" -> project.rootProject
        project.rootProject.name == "build-logic" -> rootProject.gradle.parent?.rootProject
        else -> project.gradle.parent?.rootProject
    }

    if (gradleRootProject != null && System.getenv("TEAMCITY_VERSION") != null) {
        val rootProjectName = rootProject.name
        val isInBuildLogic = rootProjectName == "build-logic"

 */
public class StorageItem {

    private final String name;
    private final String path;
    private final boolean directory;
    private final long size;
    private final ZonedDateTime lastModified;
    private final String encodedId;

    /**
     * Creates a new StorageItem instance.
     *
     * @param name the name of the item
     * @param path the path of the item

# Field name for content minhash bits in the index.
index.field.content_minhash_bits=content_minhash_bits
# Field name for cache in the index.
index.field.cache=cache
# Field name for digest in the index.
index.field.digest=digest
# Field name for title in the index.
index.field.title=title
# Field name for host in the index.
index.field.host=host
# Field name for site in the index.
index.field.site=site