### 无返回类型 { #no-return-type }

你也可以省略返回类型。此时 FastAPI 会使用 [`jsonable_encoder`](./encoder.md) 将数据转换为可序列化为 JSON 的形式，然后以 JSON Lines 发送。

{* ../../docs_src/stream_json_lines/tutorial001_py310.py ln[33:36] hl[34] *}

## 服务器发送事件（SSE） { #server-sent-events-sse }

Klaus Post <******@****.***> 1756435188 +0200

Rene Groeschke <******@****.***> 1622539170 +0200

		wantpos int64
		readerr error
		seekerr string
	}{
		{seek: io.SeekStart, off: 0, n: 20, want: "0123456789"},
		{seek: io.SeekStart, off: 1, n: 1, want: "1"},
		{seek: io.SeekCurrent, off: 1, wantpos: 3, n: 2, want: "34"},
		{seek: io.SeekStart, off: -1, seekerr: "bytes.Reader.Seek: negative position"},
		{seek: io.SeekStart, off: 1 << 33, wantpos: 1 << 33, readerr: io.EOF},
		{seek: io.SeekCurrent, off: 1, wantpos: 1<<33 + 1, readerr: io.EOF},

        // Word count
        buffer[32] = 10; // 10 words = 20 bytes

        // Parameter words for transaction response
        // Total parameter count (2 bytes)
        buffer[33] = 0x00;
        buffer[34] = 0x00;

        // Total data count (2 bytes)
        buffer[35] = 0x00;
        buffer[36] = 0x00;

        // Reserved (2 bytes)
        buffer[37] = 0x00;
        buffer[38] = 0x00;

        byte[] dst = new byte[256];
        int bytesWritten = packet.writeTrailerWireFormat(dst, 0);

        assertTrue(bytesWritten > 0);
        // Each name should write at least 34 bytes (encoded name + scope)
        assertTrue(bytesWritten >= 68);
    }

    @Test
    @DisplayName("writeTrailerWireFormat with scope should handle scoped names")
    void testWriteTrailerWireFormatWithScope() {

### 不宣告回傳型別 { #no-return-type }

你也可以省略回傳型別。此時 FastAPI 會使用 [`jsonable_encoder`](./encoder.md) 將資料轉換為可序列化為 JSON 的形式，然後以 JSON Lines 傳送。

{* ../../docs_src/stream_json_lines/tutorial001_py310.py ln[33:36] hl[34] *}

## 伺服器推播事件（SSE） { #server-sent-events-sse }

    assertThat(formEncode(31)).isEqualTo("%1F")
    // Browsers use '+' for space.
    assertThat(formEncode(32)).isEqualTo("+")
    assertThat(formEncode(33)).isEqualTo("%21")
    assertThat(formEncode(34)).isEqualTo("%22")
    assertThat(formEncode(35)).isEqualTo("%23")
    assertThat(formEncode(36)).isEqualTo("%24")
    assertThat(formEncode(37)).isEqualTo("%25")
    assertThat(formEncode(38)).isEqualTo("%26")

### 戻り値の型なし { #no-return-type }

戻り値の型を省略することもできます。FastAPI はその場合、データを JSON にシリアライズ可能な形に変換するために [`jsonable_encoder`](./encoder.md) を使い、JSON Lines として送信します。

{* ../../docs_src/stream_json_lines/tutorial001_py310.py ln[33:36] hl[34] *}

## Server-Sent Events (SSE) { #server-sent-events-sse }

            return ++i;
          }
        };

    cache.put(0, 10);

    assertThat(cache.get(0, loader)).isEqualTo(10);
    assertThat(cache.get(20, loader)).isEqualTo(1);
    assertThat(cache.get(34, loader)).isEqualTo(2);

    cache.invalidate(0);
    assertThat(cache.get(0, loader)).isEqualTo(3);

    cache.put(0, 10);
    cache.invalidateAll();
    assertThat(cache.get(0, loader)).isEqualTo(4);
  }