We think you have liked this presentation. If you wish to download it, please recommend it to your friends in any social system. Share buttons are a little bit lower. Thank you!
Presentation is loading. Please wait.
Published byLandon Gill
Modified over 3 years ago
The State of the Python Union OSCON – August 3, 2005 Guido van Rossum Elemental Security, Inc.
August © 2005 Guido van Rossum 3
August © 2005 Guido van Rossum 4
August © 2005 Guido van Rossum 6 Elemental Security, Inc. Enterprise security software express, monitor and enforce security policies for any computer connecting to the network (cross-platform) scored 9.3 in recent InfoWorld Test Center Startup (no longer in stealth mode!) C round just closed; 11M led by Lehman Brothers Using lots of Python (and Java!) We're always hiring! See Now a real website :-)
August © 2005 Guido van Rossum 7 Elemental Security and Python Paid for Python port to HP-UX on Itanium2 –Giving back to PSF, of course! –AIX 5.3 to follow shortly Also plan to contribute: –ElementClass (yet another XML tool :-) –pgen reimplemented in Python –yeah, I know, I promised these last year too... Talk Wednesday (09:30 in VB) –"What I did last year"
August © 2005 Guido van Rossum 8 The Python Software Foundation Holds and protects the IP (©, ®) behind Python Makes PyCon possible by taking the financial risk Funds grants, e.g. Jython grant and python.org redevelopment Participates in Google's Summer of Code There are 750K+ Python programmers –if 1% gave $100/yr (or 10% gave $10/yr) we would have $750K/year budget
August © 2005 Guido van Rossum 10 Python's Growing Popularity 14% (from 8%) – InfoWorld survey (Sept '04) –"But the big winner this time around is the object- oriented scripting language Python, which saw a 6 percent gain in popularity, almost doubling last year's results. " Burton Group report on "P-languages": –"Both Perl and Python have been used in application development and for limited integration, but it appears that Python is a better fit for this domain for several reasons. Python is easy to learn, fully functional, syntactically clean, and very modular. " Report available for $$ via Tim O'Reilly: Python book sales are gaining on Perl!
August © 2005 Guido van Rossum 11 Jolt Productivity Award for Python Category: Languages and Development Tools Runner-up, shared with IntelliJ & RealBasic Category winner: Eclipse SD Magazine & Conference Second time around (last time won was in 2000)
August © 2005 Guido van Rossum 12 Python.org Growth Feb 2004 python.org traffic: –793K visits from 421K sites (1.0 TB) Feb 2005 python.org traffic: –1023K visits from 473K sites (1.3 TB) Growth in one year: –visits +29%, originating sites +12%, data +30% –and Feb 2004 had a leap day :-)
August © 2005 Guido van Rossum 13 O'Reilly CodeZoo Now with Python section!
August © 2005 Guido van Rossum 14 Languages Used on SourceForge data = "..." # scraped from SF website import re lines = [line.strip() for line in data.splitlines()] lines = [line for line in lines if line] table =  for line in lines: m = re.match("(.*)\s\((\d+) projects\)", line) if m: table.append((int(m.group(2)), m.group(1))) table.sort() table.reverse() for count, language in table: print "%6d %s" % (count, language)
August © 2005 Guido van Rossum 17 PEP 342 and PEP 343 Discussion on python-dev broke all records Results are really nice PEP 342 adds generator enhancements –patch by Phillip Eby just checked in (needs work) PEP 343 adds with-statement –no patch yet Both PEPs accepted at EuroPython last month
August © 2005 Guido van Rossum 18 QOFT "I still haven't gotten used to Guido's heart-attack inducing early enthusiasm for strange things followed later by a simple proclamation I like. Some day I'll learn that the sound of fingernails on the chalkboard is frequently followed by candy for the whole class." –Jack Diederich
August © 2005 Guido van Rossum 19 PEP 342: Generator Enhancements yield-expression instead of yield-statement –x = yield a, b, c –print (yield abc) –"yield" is equivalent to "yield None" g.send(value) causes yield to return value –g.send(None) is equivalent to g.next() –initial call must be next() or g.send(None) g.throw(exc, [val, [tb]]) causes yield to raise exc g.close(): throws GeneratorExit; called by GC yield is now allowed inside try/finally
August © 2005 Guido van Rossum 20 What Does This Buy Us? More coroutine-like functionality Natural asynchronous event handling Generators can emulate lightweight threads Twisted example (from memory): d = Deferred(...) w = WaitForDeferred(d) yield w data = w.getResult()...use data... –becomes: d = Deferred(...) data = yield d...use data...
August © 2005 Guido van Rossum 21 PEP 343: The With-Statement with EXPR [as VAR]: BLOCK Translation: abc = EXPR [VAR =] abc.__enter__() try: BLOCK finally: abc.__exit__(...) The... mean that __exit__() is called as follows: –if BLOCK raised exception, __exit__(*sys.exc_info()) –otherwise, __exit__(None, None, None) I'm no longer favoring Pascal-style with-statement
August © 2005 Guido van Rossum 22 What Does This Buy Us? No excuse any more to write this: mutex.acquire()...critical section code... mutex.release() (See the bug?) Because this is less typing: with mutex:...critical section code... Observation: –using try/finally blocks is often a requirement of an API rather than a choice for that API's user –at least when you use try/except anywhere else
August © 2005 Guido van Rossum 23 Rejected PEPs Raymond Hettinger pushed me to pronounce on these: PEP 336 – Make None Callable PEP 313 – Roman Numerals PEP 303 – Extended divmod() PEP 284 – Integer for-loops PEP 281 – Loop counter iteration with [x]range() PEP 276 – Simple iterator for ints PEP 274 – Dict Comprehensions (withdrawn by author) PEP 265 – Sorting Dictionaries by Value PEP 239, 240 – Rational Type and Rational Literal Several others superseded by PEPs 342/343 –288, 310, 319, 325, 340, 346
August © 2005 Guido van Rossum 24 Hopeful PEPs PEP 3000 – Python 3.0 Plans PEP 344 – Exception Chaining & Embedded Tracebacks PEP 341 – Unifying try/except/finally (accepted) PEP 315 – do-while statement PEP 246 – Adaptation (won't die, won't commit :-) not quite PEP 245 – Interface declarations PEP-to-be-named – Exception Reform Probably others, but I've been too busy to check
August © 2005 Guido van Rossum 25 Exception Reform Proposal PEP by Brett Cannon forthcoming Bare 'except:' catches StandardError Exceptions must derive from 'Exception' Some restructuring of the hierarchy Some new exceptions Some new inheritance Rename some exceptions Deprecate WindowsError Use multiple inheritance for compatibility period Discussion is still ongoing!!!
August © 2005 Guido van Rossum 26 Possible New Exception Hierarchy Exception + ControlFlowException (new) + StopIteration + GeneratorExit + SystemExit + CriticalError (new) + KeyboardInterrupt + MemoryError + SystemError + StandardError + AssertionError + SyntaxError + IndentationError + TabError + UserError (rename of RuntimeError) + ArithmeticError + FloatingPointError + DivideByZeroError + OverflowError + UnicodeError + UnicodeDecodeError + UnicodeEncodeError + UnicodeTranslateError + LookupError + IndexError + KeyError + TypeError + AttributeError + EnvironmentError + OSError + IOError + EOFError (new inheritance) + socket.error (new inheritance) + select.error (new inheritance) + ImportError + NotImplementedError (new inheritance) + NamespaceError (rename of NameError) + UnboundGlobalError (new) + UnboundLocalError + UnboundFreeError (new) + ValueError + Warning + UserWarning + AnyDeprecationWarning (new) + PendingDeprecationWarning + DeprecationWarning + SyntaxWarning + SemanticsWarning (rename of RuntimeWarning) + FutureWarning + WeakReferenceError (rename of ReferenceError) + WindowsError (deleted)
August © 2005 Guido van Rossum 27 Python 3000 (To be clear: this is the same as Python 3.0) Not "second system syndrome done right" In particular, not rewriting CPython from scratch More likely, various Py3k features will show up in Python 2.5, 2.6,...; some directly, some with a __future__ import Python 3.0 will be incompatible with Python 2.9 Focus on language + library, not implementation Library restructuring needs a champion! Many VMs competing: Jython, IronPython, Parrot,...
August © 2005 Guido van Rossum 28 Optional Type Declarations The controversial topic that keeps coming back! See my blogs of last December – January Mostly in support for documentation, IDEs No compile-time checking (but can help PyChecker) Perhaps no run-time semantics (docs only) Perhaps adaptation-based semantics –customizable by overriding __typecheck__ should probably rename this (to what?) –see blogs for details Perhaps most useful in interface declarations
August © 2005 Guido van Rossum 29 My Favorite Syntax def f(x: str, y: list[int], z: file|None = None)->bool:... Full syntax for an argument: –ARG ::= NAME [':' EXPR] ['=' EXPR] –Possibly also for (esp. instance) variables x[y] and x|y operators supported by type metaclass –x[y] probably only for container types (e.g. list, dict) –x[y, z,...] supported too –user-defined types (classes) can do this too Variables in type expressions resolved at run-time –(at function definition time, like default expressions)
August © 2005 Guido van Rossum 30 Rejected Syntax Alternatives ARG ::= NAME as TYPE –VB style –PEP 343 uses 'as' very differently (with EXPR as VAR) ARG ::= TYPE NAME –C/C++/Java/C# style –ambiguous as soon as TYPE is more than a name ARG ::= TYPE(NAME) –Pythonic cast style (my name for it) –doesn't read well when TYPE is list[int] or file|None
August © 2005 Guido van Rossum 32 Python Release Schedule "the plan is still for a in mid-September" –Anthony Baxter (release manager)
August © 2005 Guido van Rossum 34
The State of the Python Union BDFL PyCon – March 24, 2005 Guido van Rossum Elemental Security, Inc.
Python Built-in Exceptions Data Fusion Albert Esterline Source:
A Crash Course Python. Python? Isn’t that a snake? Yes, but it is also a...
Lecture 07 – Exceptions. Understand the flow of control that occurs with exceptions try, except, finally Use exceptions to handle unexpected runtime.
An Introduction to Python and Its Use in Bioinformatics Csc 487/687 Computing for Bioinformatics.
Optional Static Typing Guido van Rossum (with Paul Prescod, Greg Stein, and the types-SIG)
Exceptions COMPSCI 105 SS 2015 Principles of Computer Science.
State of the Python Union OSCON Portland, Oregon July 29, 2004 Guido van Rossum Elemental Security, Inc.
Python 3000 (PyCon, 24-Feb-02007) Guido van Rossum
Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-Wesley Chapter 12 Introduction to ASP.NET.
Why I Invented Python EuroPython – June 27, 2005 Guido van Rossum Elemental Security, Inc.
Python at Elemental Security EuroPython - June 29, 2005 Guido van Rossum Elemental Security, Inc.
CMPT 120 Functions and Decomposition Summer 2012 Instructor: Hassan Khosravi.
Lilian Blot VARIABLE SCOPE EXCEPTIONS FINAL WORD Final Lecture Spring 2014 TPOP 1.
Chapter 9 Interactive Multimedia Authoring with Flash Introduction to Programming 1.
Languages for IT & CS Pseudo-code What HTML isn’t Early history Compiling & interpreting Classifying languages The process of programming.
1 Semantic Analysis and Symbol Tables. 2 Outline How to build symbol tables How to use them to find –multiply-declared vars –undeclared vars How to perform.
CS1022 Computer Programming & Principles Lecture 2.1 A brief introduction to Python (1)
Error-handling using exceptions Contents: Types of errors Minimizing errors by using control statements and the Debug class Exceptions, Throwing and catching.
"The State of the Python Union" Python10 - Alexandria, VA - February 7, 2002 Guido van Rossum Director, PythonLabs at Zope Corporation
AJDT and AspectJ Release Review | © 2007 by SpringSource, made available under the EPL v1.0 1 Release Review: AJDT and AspectJ
40 Tips Leveraging the New APICS.org to the Benefit of Your Organization, Members, and Customers! 1.
Cem Sahin CS There are two distinguishable kinds of errors: Python's Errors Syntax ErrorsExceptions.
User Defined Functions Lesson 1 CS1313 Fall User Defined Functions 1 Outline 1.User Defined Functions 1 Outline 2.Standard Library Not Enough #1.
Exception Handling Genome 559. Review - classes 1) Class constructors - class myClass: def __init__(self, arg1, arg2): self.var1 = arg1 self.var2 = arg2.
1 VBScript Session What we learn last session?
A Second Look At ML Chapter SevenModern Programming Languages, 2nd ed.1.
State of the Python Union OSCON, July 24, 2002 Guido van Rossum Director of PythonLabs at Zope Corporation
© 2012 National Heart Foundation of Australia. Slide 2.
Python Overview Last week Python 3000 was released Python 3000 == Python 3.0 == Py3k Designed to break backwards compatibility with the 2.x.
Januar 2005 S M T O T F L
©Brooks/Cole, 2001 Chapter 12 Derived Types-- Enumerated, Structure and Union.
© Paradigm Publishing, Inc Excel 2013 Level 2 Unit 2Managing and Integrating Data and the Excel Environment Chapter 8Importing, Exporting, and Distributing.
Chapter 7 Constructors and Other Tools. Copyright © 2006 Pearson Addison-Wesley. All rights reserved. 7-2 Learning Objectives Constructors Definitions.
Python: 2 or 3? Bruce Beckles University of Cambridge Computing Service.
Implementing Domain Decompositions Intel Software College Introduction to Parallel Programming – Part 3.
3 Copyright © 2005, Oracle. All rights reserved. Basic Java Syntax and Coding Conventions.
Chapter 12: Pointers and Arrays Copyright © 2008 W. W. Norton & Company. All rights reserved. 1 Chapter 12 Pointers and Arrays.
1 Final and Abstract Classes. 2 Restricting Inheritance Parent Child Inherited capability.
2003 Prentice Hall, Inc. All rights reserved. 1 Chapter 13 - Exception Handling Outline 13.1 Introduction 13.2 Exception-Handling Overview 13.3 Other.
McDonald’s calendar 2009 January
1 Chapter 8 Improving the User Interface Fundamentals of Java: AP Computer Science Essentials, 4th Edition Lambert / Osborne.
Python 3000 and You Guido van Rossum PyCon March 14, 2008.
Chapter 1 Object Oriented Programming 1. OOP revolves around the concept of an objects. Objects are created using the class definition. Programming techniques.
Copyright © 2003 Pearson Education, Inc. Slide 8-1 Created by Cheryl M. Hughes, Harvard University Extension School Cambridge, MA The Web Wizards Guide.
VistA Imaging Capture via Import. 2October 2007 The information in this documentation includes only new and updated functionality of the software after.
© Copyright by Deitel & Associates, Inc. and Pearson Education Inc. All Rights Reserved. 1 Tutorial 12 – Security Panel Application Introducing.
© 2017 SlidePlayer.com Inc. All rights reserved.