Traits User Manual
Previous: 4.4 Notification with Deferring Table of Contents Next: 5.1 Trait Subclassing
Traits User Manual
1 Introduction
1.1 What Are Traits?
1.2 Background
2 Defining Traits: Initialization and Validation
2.1 Predefined Traits
2.1.1 Predefined Traits for Simple Types
2.1.2 Other Predefined Traits
2.2 Trait Metadata
2.2.1 Internal Metadata Attributes
2.2.2 Recognized Metadata Attributes
2.2.3 Accessing Metadata Attributes
3 Trait Notification
3.1 Dynamic Notification
3.1.1 Example of a Dynamic Notification Handler
3.1.2 The name Parameter
3.1.3 Notification Handler Signatures
3.1.4 Dynamic Handler Special Cases
3.2 Static Notification
3.2.1 Handler Decorator
3.2.2 Specially-named Notification Handlers
3.2.3 Attribute-specific Handler Signatures
3.2.4 General Static Handler Signatures
3.3 Trait Events
3.4 Undefined Object
4 Deferring Trait Definitions
4.1 DelegatesTo
4.2 PrototypedFrom
4.3 Keyword Parameters
4.3.1 Prefix Keyword
4.3.2 Listenable Keyword
4.4 Notification with Deferring
5 Custom Traits
5.1 Trait Subclassing
5.1.1 Defining a Trait Type
5.1.2 Defining a Trait Property
5.1.3 Other TraitType Members
5.2 The Trait() Factory Function
5.2.1 Trait () Parameters
5.2.2 Mapped Traits
5.3 Trait Handlers
5.3.1 TraitPrefixList
5.3.2 TraitPrefixMap
5.4 Custom Trait Handlers
5.4.1 Example Custom Trait Handler
6 Advanced Topics
6.1 Initialization and Validation Revisited
6.1.1 Dynamic Initialization
6.1.2 Overriding Default Values in a Subclass
6.1.3 Reusing Trait Definitions
6.1.4 Trait Attribute Definition Strategies
6.1.5 Type-Checked Methods
6.2 Interfaces
6.2.1 Defining an Interface
6.2.2 Implementing an Interface
6.2.3 Using Interfaces
6.3 Adaptation
6.3.1 Defining Adapters
6.3.2 Using Adapters
6.3.3 Controlling Adaptation
6.4 Property Traits
6.4.1 Property Factory Function
6.4.2 Caching a Property Value
6.5 Persistence
6.5.1 Pickling HasTraits Objects
6.5.2 Predefined Transient Traits
6.5.3 Overriding __getstate__()
6.5.4 Unpickling HasTraits Objects
6.5.5 Overriding __setstate__()
6.6 Useful Methods on HasTraits
6.6.1 add_trait()
6.6.2 clone_traits()
6.6.3 set()
6.6.4 add_class_trait()
6.7 Performance Considerations of Traits

5      Custom Traits

The predefined traits such as those described in Section 2.1 are handy shortcuts for commonly used types. However, the Traits package also provides facilities for defining complex or customized traits:

·    Subclassing of traits

·    The Trait() factory function

·    Predefined or custom trait handlers

Previous: 4.4 Notification with Deferring Table of Contents Next: 5.1 Trait Subclassing
Traits User Manual