// definition for OkHttp's host header checks (and the WHATWG Host syntax definition). Here
    // we rule out characters that would cause problems in host headers.
    if (c <= '\u001f' || c >= '\u007f') {
      return true
    }
    // Check for the characters mentioned in the WHATWG Host parsing spec:

Todas las dependencias que hemos visto son una función o clase fija.

Pero podría haber casos en los que quieras poder establecer parámetros en la dependencia, sin tener que declarar muchas funciones o clases diferentes.

Imaginemos que queremos tener una dependencia que revise si el parámetro de query `q` contiene algún contenido fijo.

Pero queremos poder parametrizar ese contenido fijo.

* **Editör desteği**.
* **Tip kontrolleri**.

...ve **FastAPI** aynı bildirimleri şunlar için de kullanır:

* **Gereksinimleri tanımlamak**: request path parameters, query parameters, headers, bodies, bağımlılıklar (dependencies), vb.
* **Veriyi dönüştürmek**: request'ten gerekli tipe.
* **Veriyi doğrulamak**: her request'ten gelen veriyi:
    * Veri geçersiz olduğunda client'a dönen **otomatik hatalar** üretmek.

}
```

/// tip

在 raise 一個 `HTTPException` 時，你可以將任何可轉為 JSON 的值作為 `detail` 參數，不只限於 `str`。

你可以傳入 `dict`、`list` 等。

**FastAPI** 會自動處理並轉為 JSON。

///

## 新增自訂標頭 { #add-custom-headers }

有些情況需要在 HTTP 錯誤回應中加入自訂標頭，例如某些安全性情境。

你大概不需要在程式碼中直接使用。

但若你在進階情境中需要，可以這樣加入自訂標頭：

{* ../../docs_src/handling_errors/tutorial002_py310.py hl[14] *}

## 安裝自訂例外處理器 { #install-custom-exception-handlers }

	// The format of the original Unix V7 tar tool prior to standardization.
	formatV7

	// FormatUSTAR represents the USTAR header format defined in POSIX.1-1988.
	//
	// While this format is compatible with most tar readers,
	// the format has several limitations making it unsuitable for some usages.
	// Most notably, it cannot support sparse files, files larger than 8GiB,
	// filenames larger than 256 characters, and non-ASCII filenames.
	//

	TypeXHeader = 'x'

	// Type 'g' is used by the PAX format to store key-value records that
	// are relevant to all subsequent files.
	// This package only supports parsing and composing such headers,
	// but does not currently support persisting the global state across files.
	TypeXGlobalHeader = 'g'

	// Type 'S' indicates a sparse file in the GNU format.
	TypeGNUSparse = 'S'

Find ways to get great performance.

Along with Hug (as Hug is based on Falcon) inspired **FastAPI** to declare a `response` parameter in functions.

Although in FastAPI it's optional, and is used mainly to set headers, cookies, and alternative status codes.

///

### [Molten](https://moltenframework.com/) { #molten }

I discovered Molten in the first stages of building **FastAPI**. And it has quite similar ideas:

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		if err := r.UnreadByte(); err == nil {
			t.Errorf("n = %d: expected error on UnreadByte", n)
		}
	}
}

func TestUnreadByteOthers(t *testing.T) {
	// A list of readers to use in conjunction with UnreadByte.
	var readers = []func(*Reader, byte) ([]byte, error){
		(*Reader).ReadBytes,
		(*Reader).ReadSlice,
		func(r *Reader, delim byte) ([]byte, error) {
			data, err := r.ReadString(delim)

            int result2 = request.encode(buffer2, 50);

            // Both should succeed independently
            assertTrue(result1 > 0);
            assertTrue(result2 > 0);

            // Verify headers in both buffers
            for (int i = 0; i < 8; i++) {
                assertEquals((byte) 0xFF, buffer1[i]);
                assertEquals((byte) 0xFF, buffer2[50 + i]);
            }
        }
    }