// Iterate over policy conditions and check them against received form fields
	for _, policy := range postPolicyForm.Conditions.Policies {
		// Form fields names are in canonical format, convert conditions names
		// to canonical for simplification purpose, so `$key` will become `Key`
		formCanonicalName := http.CanonicalHeaderKey(strings.TrimPrefix(policy.Key, "$"))
		// Operator for the current policy condition
		op := policy.Operator

}

// SetAccessKey sets access key as jwt subject and custom
// "accessKey" field.
func (c *StandardClaims) SetAccessKey(accessKey string) {
	c.Subject = accessKey
	c.AccessKey = accessKey
}

// Valid - implements https://godoc.org/github.com/golang-jwt/jwt#Claims compatible
// claims interface, additionally validates "accessKey" fields.
func (c *StandardClaims) Valid() error {

    delegate.addListener(fire, directExecutor());
    return result;
  }

  /*
   * Memory visibility of these fields. There are two cases to consider.
   *
   * 1. visibility of the writes to these fields to Fire.run:
   *
   * The initial write to delegateRef is made definitely visible via the semantics of

	user, err := schema.Parse(&UserWithPermissionControl{}, &sync.Map{}, schema.NamingStrategy{})
	if err != nil {
		t.Fatalf("Failed to parse user with permission, got error %v", err)
	}

	fields := []*schema.Field{
		{Name: "ID", DBName: "id", BindNames: []string{"ID"}, DataType: schema.Uint, PrimaryKey: true, Size: 64, Creatable: true, Updatable: true, Readable: true, HasDefaultValue: true, AutoIncrement: true},

```

////

//// tab | Python 3.8+

```Python hl_lines="15-23"
{!> ../../docs_src/schema_extra_example/tutorial001.py!}
```

////

这些额外的信息将按原样添加到输出的JSON模式中。

## `Field` 的附加参数

在 `Field`, `Path`, `Query`, `Body` 和其他你之后将会看到的工厂函数，你可以为JSON 模式声明额外信息，你也可以通过给工厂函数传递其他的任意参数来给JSON 模式声明额外信息，比如增加 `example`:

//// tab | Python 3.10+

```Python hl_lines="2  8-11"

func (z *xlMetaDataDirDecoder) DecodeMsg(dc *msgp.Reader) (err error) {
	var field []byte
	_ = field
	var zb0001 uint32
	zb0001, err = dc.ReadMapHeader()
	if err != nil {
		err = msgp.WrapError(err)
		return
	}
	var zb0001Mask uint8 /* 1 bits */
	_ = zb0001Mask
	for zb0001 > 0 {
		zb0001--
		field, err = dc.ReadMapKeyPtr()
		if err != nil {
			err = msgp.WrapError(err)
			return
		}

            int domainIdPointer = pacStream.readInt();

            // Skip some reserved fields
            pacStream.skipBytes(8);

            this.userAccountControl = pacStream.readInt();

            // Skip some reserved fields
            pacStream.skipBytes(28);

            // Extra SIDs information
            int extraSidCount = pacStream.readInt();

	AuthToken  string          `json:"authToken"`
	Transport  *http.Transport `json:"-"`
	ClientCert string          `json:"clientCert"`
	ClientKey  string          `json:"clientKey"`
}

// Validate WebhookArgs fields
func (w WebhookArgs) Validate() error {
	if !w.Enable {
		return nil
	}
	if w.Endpoint.IsEmpty() {
		return errors.New("endpoint empty")
	}

			// incorrectly believed that the old GNU format had a prefix field.
			// This is wrong and leads to an output file that mangles the
			// atime and ctime fields, which are often left unused.
			//
			// In order to continue reading tar files created by former, buggy
			// versions of Go, we skeptically parse the atime and ctime fields.
			// If we are unable to parse them and the prefix field looks like

```

その追加情報はそのまま出力され、JSON Schemaに追加されます。

## `Field`の追加引数

後述する`Field`、`Path`、`Query`、`Body`などでは、任意の引数を関数に渡すことでJSON Schemaの追加情報を宣言することもできます:

```Python hl_lines="4 10 11 12 13"
{!../../docs_src/schema_extra_example/tutorial002.py!}
```

/// warning | "注意"

これらの追加引数が渡されても、文書化のためのバリデーションは追加されず、注釈だけが追加されることを覚えておいてください。

///

## `Body`の追加引数

追加情報を`Field`に渡すのと同じように、`Path`、`Query`、`Body`などでも同じことができます。