// responseDefinition returns true and current context if it is a ResponseDefinition,
// nil and false otherwise.
func responseDefinition(failIfNotResponse bool) (*design.ResponseDefinition, bool) {
	r, ok := dslengine.CurrentDefinition().(*design.ResponseDefinition)
	if !ok && failIfNotResponse {
		dslengine.IncompatibleDSL(dslengine.Caller())
	}
	return r, ok
}

// attribute returns true and current context if it is an Attribute,
// nil and false otherwise.
func attributeDefinition(failIfNotAttribute bool) (*design.AttributeDefinition, bool) {
	a, ok := dslengine.CurrentDefinition().(*design.AttributeDefinition)
	if !ok && failIfNotAttribute {
		dslengine.IncompatibleDSL(dslengine.Caller())
	}
	return a, ok
}

// actionDefinition returns true and current context if it is an ActionDefinition,
// nil and false otherwise.
func actionDefinition(failIfNotAction bool) (*design.ActionDefinition, bool) {
	a, ok := dslengine.CurrentDefinition().(*design.ActionDefinition)
	if !ok && failIfNotAction {
		dslengine.IncompatibleDSL(dslengine.Caller())
	}
	return a, ok
}

// typeDefinition returns true and current context if it is a UserTypeDefinition,
// nil and false otherwise.
func typeDefinition(failIfNotMT bool) (*design.UserTypeDefinition, bool) {
	m, ok := dslengine.CurrentDefinition().(*design.UserTypeDefinition)
	if !ok && failIfNotMT {
		dslengine.IncompatibleDSL(dslengine.Caller())
	}
	return m, ok
}

// docsDefinition returns true and current context if it is a DocsDefinition,
// nil and false otherwise.
func docsDefinition(failIfNotDocs bool) (*design.DocsDefinition, bool) {
	a, ok := dslengine.CurrentDefinition().(*design.DocsDefinition)
	if !ok && failIfNotDocs {
		dslengine.IncompatibleDSL(dslengine.Caller())
	}
	return a, ok
}

// licenseDefinition returns true and current context if it is an APIDefinition,
// nil and false otherwise.
func licenseDefinition(failIfNotLicense bool) (*design.LicenseDefinition, bool) {
	l, ok := dslengine.CurrentDefinition().(*design.LicenseDefinition)
	if !ok && failIfNotLicense {
		dslengine.IncompatibleDSL(dslengine.Caller())
	}
	return l, ok
}

// contactDefinition returns true and current context if it is an ContactDefinition,
// nil and false otherwise.
func contactDefinition(failIfNotContact bool) (*design.ContactDefinition, bool) {
	a, ok := dslengine.CurrentDefinition().(*design.ContactDefinition)
	if !ok && failIfNotContact {
		dslengine.IncompatibleDSL(dslengine.Caller())
	}
	return a, ok
}

// encodingDefinition returns true and current context if it is an EncodingDefinition,
// nil and false otherwise.
func encodingDefinition(failIfNotEnc bool) (*design.EncodingDefinition, bool) {
	e, ok := dslengine.CurrentDefinition().(*design.EncodingDefinition)
	if !ok && failIfNotEnc {
		dslengine.IncompatibleDSL(dslengine.Caller())
	}
	return e, ok
}

// Attribute implements the attribute definition DSL. An attribute describes a data structure
// recursively. Attributes are used for describing request headers, parameters and payloads -
// response bodies and headers - media types	 and types. An attribute definition is recursive:
// attributes may include other attributes. At the basic level an attribute has a name,
// a type and optionally a default value and validation rules. The type of an attribute can be one of:
//
// * The primitive types Boolean, Integer, Number or String.
//
// * A type defined via the Type function.
//
// * A media type defined via the MediaType function.
//
// * An object described recursively with child attributes.
//
// * An array defined using the ArrayOf function.
//
// * An hashmap defined using the HashOf function.
//
// Attributes can be defined using the Attribute, Param, Member or Header functions depending
// on where the definition appears. The syntax for all these DSL is the same.
// Here are some examples:
//
//	Attribute("name")					// Defines an attribute of type String
//
//	Attribute("name", func() {
//		Pattern("^foo")					// Adds a validation rule to the attribute
//	})
//
//	Attribute("name", Integer)				// Defines an attribute of type Integer
//
//	Attribute("name", Integer, func() {
//		Default(42)					// With a default value
//	})
//
//	Attribute("name", Integer, "description")		// Specifies a description
//
//	Attribute("name", Integer, "description", func() {
//		Enum(1, 2)					// And validation rules
//	})
//
// Nested attributes:
//
//	Attribute("nested", func() {
//		Description("description")
//		Attribute("child")
//		Attribute("child2", func() {
//			// ....
//		})
//		Required("child")
//	})
//
// Here are all the valid usage of the Attribute function:
//
//	Attribute(name string, dataType DataType, description string, dsl func())
//
//	Attribute(name string, dataType DataType, description string)
//
//	Attribute(name string, dataType DataType, dsl func())
//
//	Attribute(name string, dataType DataType)
//
//	Attribute(name string, dsl func())	// dataType is String or Object (if DSL defines child attributes)
//
//	Attribute(name string)			// dataType is String
func Attribute(name string, args ...interface{}) {
	var parent *design.AttributeDefinition
	if at, ok := attributeDefinition(false); ok {
		parent = at
	} else if mt, ok := mediaTypeDefinition(false); ok {
		parent = mt.AttributeDefinition
	} else if c, ok := dslengine.CurrentDefinition().(design.ContainerDefinition); ok {
		parent = c.Attribute()
	} else {
		dslengine.IncompatibleDSL(dslengine.Caller())
	}

	if parent != nil {
		if parent.Type == nil {
			parent.Type = design.Object{}
		}
		if _, ok := parent.Type.(design.Object); !ok {
			dslengine.ReportError("can't define child attributes on attribute of type %s", parent.Type.Name())
			return
		}

		var baseAttr *design.AttributeDefinition
		if parent.Reference != nil {
			if att, ok := parent.Reference.ToObject()[name]; ok {
				baseAttr = design.DupAtt(att)
			}
		}

		dataType, description, dsl := parseAttributeArgs(baseAttr, args...)
		if baseAttr != nil {
			if description != "" {
				baseAttr.Description = description
			}
			if dataType != nil {
				baseAttr.Type = dataType
			}
//.........这里部分代码省略.........