world 5 3 Threads and WSGI 7 4 asyncio Integration 9 5 Installation 11 6 Documentation 13 6.1 User’s guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . for long polling, WebSockets, and other applications that require a long-lived connection to each user. CONTENTS 1Tornado Documentation, Release 6.5.1 2 CONTENTSCHAPTER ONE QUICK LINKS • Current version: frameworks. It is not based on WSGI, and it is typically run with only one thread per process. See the User’s guide for more on Tornado’s approach to asynchronous programming. While some support of WSGI is

wikipedia.org/wiki/WebSocket], and other applications that require a long-lived connection to each user. Quick links Current version: 6.5.1 (download from PyPI [https://pypi.python.org/pypi/tornado], [https://wsgi.readthedocs.io/en/latest/], and it is typically run with only one thread per process. See the User’s guide for more on Tornado’s approach to asynchronous programming. While some support of WSGI is it is not a focus of development and most applications should be written to use Tornado’s own interfaces (such as tornado.web) directly instead of using WSGI. In general, Tornado code is not thread-safe

Promotion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 195 16 Interfaces 199 16.1 Iteration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . dynamic languages as being "typeless", they are definitely not. Every object, whether primitive or user-defined, has a type. The lack of type declarations in most dynamic lan- guages, however, means that object-oriented dispatch. Operators are just functions with special notation – to extend addition to new user-defined data types, you define new methods for the + function. Existing code then seamlessly applies

Promotion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 195 16 Interfaces 199 16.1 Iteration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . dynamic languages as being "typeless", they are definitely not. Every object, whether primitive or user-defined, has a type. The lack of type declarations in most dynamic lan- guages, however, means that object-oriented dispatch. Operators are just functions with special notation – to extend addition to new user-defined data types, you define new methods for the + function. Existing code then seamlessly applies

Promotion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 195 16 Interfaces 199 16.1 Iteration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . dynamic languages as being "typeless", they are definitely not. Every object, whether primitive or user-defined, has a type. The lack of type declarations in most dynamic lan- guages, however, means that object-oriented dispatch. Operators are just functions with special notation – to extend addition to new user-defined data types, you define new methods for the + function. Existing code then seamlessly applies

Promotion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185 15 Interfaces 189 15.1 Iteration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . dynamic languages as being "typeless", they are definitely not. Every object, whether primitive or user-defined, has a type. The lack of type declarations in most dynamic lan- guages, however, means that object-oriented dispatch. Operators are just functions with special notation – to extend addition to new user-defined data types, you define new methods for the + function. Existing code then seamlessly applies

Promotion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185 15 Interfaces 189 15.1 Iteration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . dynamic languages as being "typeless", they are definitely not. Every object, whether primitive or user-defined, has a type. The lack of type declarations in most dynamic lan- guages, however, means that object-oriented dispatch. Operators are just functions with special notation – to extend addition to new user-defined data types, you define new methods for the + function. Existing code then seamlessly applies

Promotion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 195 16 Interfaces 199 16.1 Iteration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . dynamic languages as being "typeless", they are definitely not. Every object, whether primitive or user-defined, has a type. The lack of type declarations in most dynamic lan- guages, however, means that 13-DEV DOCUMENTATION 4 Operators are just functions with special notation – to extend addition to new user-defined data types, you define new methods for the + function. Existing code then seamlessly applies

Promotion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 195 16 Interfaces 199 16.1 Iteration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . dynamic languages as being "typeless", they are definitely not. Every object, whether primitive or user-defined, has a type. The lack of type declarations in most dynamic lan- guages, however, means that 12-RC1 DOCUMENTATION 4 Operators are just functions with special notation – to extend addition to new user-defined data types, you define new methods for the + function. Existing code then seamlessly applies

Promotion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 195 16 Interfaces 199 16.1 Iteration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . dynamic languages as being "typeless", they are definitely not. Every object, whether primitive or user-defined, has a type. The lack of type declarations in most dynamic lan- guages, however, means that 12-BETA4 DOCUMENTATION 4 Operators are just functions with special notation – to extend addition to new user-defined data types, you define new methods for the + function. Existing code then seamlessly applies