CONTENTS 1Tornado Documentation, Release 6.5.1 2 CONTENTSCHAPTER ONE QUICK LINKS • Current version: 6.5.1 (download from PyPI, release notes) • Source (GitHub) • Mailing lists: discussion and announcements optional packages may be useful: • pycurl is used by the optional tornado.curl_httpclient. Libcurl version 7.22 or higher is required. • pycares is an alternative non-blocking DNS resolver that can be used yield expressions, and with the coroutine’s caller by returning a Future. Here is a simplified version of the coroutine decorator’s inner loop: # Simplified inner loop of tornado.gen.Runner def run(self):

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], release notes) Source (GitHub) may be useful:pycurl [http://pycurl.io/] is used by the optional tornado.curl_httpclient. Libcurl version 7.22 or higher is required. pycares [https://pypi.org/project/pycares/] is an alternative non-blocking google.com/forum/#!forum/python- tornado-announce]. Tornado is available under the Apache License, Version 2.0 [http://www.apache.org/licenses/LICENSE-2.0.html]. This web site and all documentation is licensed

Byte Array Literals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68 8.11 Version Number Literals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69 8.12 Raw String 19 Further Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93 10 Control Flow 94 10.1 Compound Expressions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Logical operators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 295 21.4 Control Flow and Short-Circuiting Operators . . . . . . . . . . . . . . . . . . . . . . 296 21.5 Arrays

Byte Array Literals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68 8.11 Version Number Literals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69 8.12 Raw String 19 Further Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93 10 Control Flow 94 10.1 Compound Expressions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Logical operators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 295 21.4 Control Flow and Short-Circuiting Operators . . . . . . . . . . . . . . . . . . . . . . 296 21.5 Arrays

Byte Array Literals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68 8.11 Version Number Literals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69 8.12 Raw String 19 Further Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93 10 Control Flow 94 10.1 Compound Expressions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Logical operators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 295 21.4 Control Flow and Short-Circuiting Operators . . . . . . . . . . . . . . . . . . . . . . 296 21.5 Arrays

Byte Array Literals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63 7.11 Version Number Literals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65 7.12 Raw String 19 Further Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88 9 Control Flow 89 9.1 Compound Expressions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Logical operators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 278 20.4 Control Flow and Short-Circuiting Operators . . . . . . . . . . . . . . . . . . . . . . 279 20.5 Arrays

Byte Array Literals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63 7.11 Version Number Literals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65 7.12 Raw String 19 Further Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88 9 Control Flow 89 9.1 Compound Expressions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Logical operators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 278 20.4 Control Flow and Short-Circuiting Operators . . . . . . . . . . . . . . . . . . . . . . 279 20.5 Arrays

Byte Array Literals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68 8.11 Version Number Literals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69 8.12 Raw String 19 Further Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93 10 Control Flow 94 10.1 Compound Expressions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Logical operators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 298 21.4 Control Flow and Short-Circuiting Operators . . . . . . . . . . . . . . . . . . . . . . 299 21.5 Arrays

Byte Array Literals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68 8.11 Version Number Literals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69 8.12 Raw String 19 Further Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93 10 Control Flow 94 10.1 Compound Expressions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Logical operators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 298 21.4 Control Flow and Short-Circuiting Operators . . . . . . . . . . . . . . . . . . . . . . 299 21.5 Arrays

Byte Array Literals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68 8.11 Version Number Literals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69 8.12 Raw String 19 Further Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93 10 Control Flow 94 10.1 Compound Expressions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Logical operators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 298 21.4 Control Flow and Short-Circuiting Operators . . . . . . . . . . . . . . . . . . . . . . 299 21.5 Arrays