@DisplayName("should return default version when model version is missing")
        void shouldReturnDefaultVersionWhenModelVersionMissing() throws Exception {
            String pomXml = """
                <?xml version="1.0" encoding="UTF-8"?>
                <project xmlns="http://maven.apache.org/POM/4.0.0">
                    <groupId>test</groupId>
                    <artifactId>test</artifactId>
                    <version>1.0.0</version>

    //
    // or we can show it graphically as:
    //
    // p1 ---> p0 --> super model
    //
    // p1 has a depMgmt section that specifies versions 1.0 of jars "a" & "b"
    // jar "a" has a transitive dependency on 2.0 of jar "b", but maven should
    // prefer to use version 1.0.
    //
    // ----------------------------------------------------------------------

    @Test

        @DisplayName("should not modify plugin when version is already sufficient")
        void shouldNotModifyPluginWhenVersionAlreadySufficient() throws Exception {
            String pomXml = """
                <?xml version="1.0" encoding="UTF-8"?>
                <project xmlns="http://maven.apache.org/POM/4.0.0">
                    <modelVersion>4.0.0</modelVersion>
                    <groupId>test</groupId>

		// apply zeros operator for this bit of len2
		gf2MatrixSquare(even, odd)
		if len2&1 != 0 {
			crc1n = gf2MatrixTimes(even, crc1n)
		}
		len2 >>= 1

		// if no more bits set, then done
		if len2 == 0 {
			break
		}

		// another iteration of the loop with odd and even swapped
		gf2MatrixSquare(odd, even)
		if len2&1 != 0 {
			crc1n = gf2MatrixTimes(odd, crc1n)
		}
		len2 >>= 1

    <dependency>
      <groupId>commons-cli</groupId>
      <artifactId>commons-cli</artifactId>
      <version>1.0-beta-2</version>
      <type>jar</type>
      <scope>compile</scope>
    </dependency>
    <dependency>
      <groupId>plexus</groupId>
      <artifactId>plexus-i18n</artifactId>
      <version>1.0-beta-2-SNAPSHOT</version>
      <type>jar</type>
      <scope>compile</scope>
    </dependency>
    <dependency>

	_ = x[ErrSTSInvalidClientGrantsToken-6]
	_ = x[ErrSTSMalformedPolicyDocument-7]
	_ = x[ErrSTSInsecureConnection-8]
	_ = x[ErrSTSInvalidClientCertificate-9]
	_ = x[ErrSTSTooManyIntermediateCAs-10]
	_ = x[ErrSTSNotInitialized-11]
	_ = x[ErrSTSIAMNotInitialized-12]
	_ = x[ErrSTSUpstreamError-13]
	_ = x[ErrSTSInternalError-14]
}

上述の例では、`skip=0` と `limit=10` というデフォルト値を持っています。

したがって、以下のURLにアクセスすることは:

```
http://127.0.0.1:8000/items/
```

以下のURLにアクセスすることと同等になります:

```
http://127.0.0.1:8000/items/?skip=0&limit=10
```

しかし、例えば、以下にアクセスすると:

```
http://127.0.0.1:8000/items/?skip=20
```

関数内のパラメータの値は以下の様になります:

* `skip=20`: URL内にセットしたため
* `limit=10`: デフォルト値

## オプショナルなパラメータ

<?xml version="1.0" encoding="UTF-8"?>

<!--
Licensed to the Apache Software Foundation (ASF) under one
or more contributor license agreements.  See the NOTICE file
distributed with this work for additional information
regarding copyright ownership.  The ASF licenses this file
to you under the Apache License, Version 2.0 (the
"License"); you may not use this file except in compliance
with the License.  You may obtain a copy of the License at

		{"test-bucket-list-object", "Asia/India/", "", SlashSeparator, 10, resultCases[27], nil, true},
		// Test with marker set as hierarchical value and with delimiter. (58-59)
		{"test-bucket-list-object", "", "Asia/India/India-summer-photos-1", SlashSeparator, 10, resultCases[28], nil, true},
		{"test-bucket-list-object", "", "Asia/India/Karnataka/Bangalore/Koramangala/pics", SlashSeparator, 10, resultCases[29], nil, true},

## 默认值

查询参数不是路径的固定内容，它是可选的，还支持默认值。

上例用 `skip=0` 和 `limit=10` 设定默认值。

访问 URL：

```
http://127.0.0.1:8000/items/
```

与访问以下地址相同：

```
http://127.0.0.1:8000/items/?skip=0&limit=10
```

但如果访问：

```
http://127.0.0.1:8000/items/?skip=20
```

查询参数的值就是：

* `skip=20`：在 URL 中设定的值
* `limit=10`：使用默认值

## 可选参数

同理，把默认值设为 `None` 即可声明**可选的**查询参数：