Re: [Tutor] decorators, __call__ (able) objects
Thanks guys, In the example the __call__ method has *args and **kws as arguments. Is that required? Also when, in what situation would you use callable objects? Cheers, T Original-Nachricht Datum: Wed, 15 Jul 2009 12:02:05 -0700 Von: wesley chun wes...@gmail.com An: vince spicer vinces1...@gmail.com, tmatsum...@gmx.net CC: Kent Johnson ken...@tds.net, tutor@python.org Betreff: Re: [Tutor] decorators, __call__ (able) objects Can some one give, or point to some good examples of how @decorators work, and __call__ (able) objects? simple example of calling a class class myKlass(object): def __call__(self, *args, **kws): print i was called test = myKlass() test() i was called close. the example was right, but the description wasn't accurate... you meant, calling an instance. i'm going to plagarize and rip this right out of section 14.1.4 from Core Python Programming: Python provides the __call__() special method for classes, which allows a programmer to create objects (instances) that are callable. By default, the __call__() method is not implemented, meaning that most instances are not callable. However, if this method is overridden in a class definition, instances of such a class are made callable. Calling such instance objects is equivalent to invoking the __call__() method. Naturally, any arguments given in the instance call are passed as arguments to __call__(). as far as decorators go, kent's tutorial is great place to start. here are 2 more articles plus PEP 318, where they were defined: http://www.ibm.com/developerworks/linux/library/l-cpdecor.html http://www.artima.com/weblogs/viewpost.jsp?thread=240808 http://www.python.org/dev/peps/pep-0318 in addition, i devoted section 11.3.6 of Core Python to decorators. finally, it should be mentioned that starting in 2.6, you can now decorate *classes*, as seen here in PEP 3129: http://www.python.org/dev/peps/pep-3129/ hope this helps! -- wesley - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Core Python Programming, Prentice Hall, (c)2007,2001 Python Fundamentals, Prentice Hall, (c)2009 http://corepython.com wesley.j.chun :: wescpy-at-gmail.com python training and technical consulting cyberweb.consulting : silicon valley, ca http://cyberwebconsulting.com -- Jetzt kostenlos herunterladen: Internet Explorer 8 und Mozilla Firefox 3 - sicherer, schneller und einfacher! http://portal.gmx.net/de/go/atbrowser ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] decorators, __call__ (able) objects
no the __call__ function can is like any function def __call__(self, passedin): or simply def __call__(self) *args and **kws explained http://www.saltycrane.com/blog/2008/01/how-to- use-args-and-kwargs-in-python/ On Thursday 16 July 2009 12:09:52 am Todd Matsumoto wrote: Thanks guys, In the example the __call__ method has *args and **kws as arguments. Is that required? Also when, in what situation would you use callable objects? Cheers, T Original-Nachricht Datum: Wed, 15 Jul 2009 12:02:05 -0700 Von: wesley chun wes...@gmail.com An: vince spicer vinces1...@gmail.com, tmatsum...@gmx.net CC: Kent Johnson ken...@tds.net, tutor@python.org Betreff: Re: [Tutor] decorators, __call__ (able) objects Can some one give, or point to some good examples of how @decorators work, and __call__ (able) objects? simple example of calling a class class myKlass(object): def __call__(self, *args, **kws): print i was called test = myKlass() test() i was called close. the example was right, but the description wasn't accurate... you meant, calling an instance. i'm going to plagarize and rip this right out of section 14.1.4 from Core Python Programming: Python provides the __call__() special method for classes, which allows a programmer to create objects (instances) that are callable. By default, the __call__() method is not implemented, meaning that most instances are not callable. However, if this method is overridden in a class definition, instances of such a class are made callable. Calling such instance objects is equivalent to invoking the __call__() method. Naturally, any arguments given in the instance call are passed as arguments to __call__(). as far as decorators go, kent's tutorial is great place to start. here are 2 more articles plus PEP 318, where they were defined: http://www.ibm.com/developerworks/linux/library/l-cpdecor.html http://www.artima.com/weblogs/viewpost.jsp?thread=240808 http://www.python.org/dev/peps/pep-0318 in addition, i devoted section 11.3.6 of Core Python to decorators. finally, it should be mentioned that starting in 2.6, you can now decorate *classes*, as seen here in PEP 3129: http://www.python.org/dev/peps/pep-3129/ hope this helps! -- wesley - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Core Python Programming, Prentice Hall, (c)2007,2001 Python Fundamentals, Prentice Hall, (c)2009 http://corepython.com wesley.j.chun :: wescpy-at-gmail.com python training and technical consulting cyberweb.consulting : silicon valley, ca http://cyberwebconsulting.com ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] decorators, __call__ (able) objects
On Wed, Jul 15, 2009 at 7:41 AM, Todd Matsumototmatsum...@gmx.net wrote: Hi, Can some one give, or point to some good examples of how @decorators work, and __call__ (able) objects? Decorators: http://personalpages.tds.net/~kent37/kk/1.html Kent ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] decorators, __call__ (able) objects
simple example of calling a class class myKlass(object): On Wed, Jul 15, 2009 at 6:33 AM, Kent Johnson ken...@tds.net wrote: On Wed, Jul 15, 2009 at 7:41 AM, Todd Matsumototmatsum...@gmx.net wrote: Hi, Can some one give, or point to some good examples of how @decorators work, and __call__ (able) objects? Decorators: http://personalpages.tds.net/~kent37/kk/1.htmlhttp://personalpages.tds.net/%7Ekent37/kk/1.html Kent ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] decorators, __call__ (able) objects
simple example of calling a class class myKlass(object): def __call__(self, *args, **kws): print i was called test = myKlass() test() i was called On Wed, Jul 15, 2009 at 6:33 AM, Kent Johnson ken...@tds.net wrote: On Wed, Jul 15, 2009 at 7:41 AM, Todd Matsumototmatsum...@gmx.net wrote: Hi, Can some one give, or point to some good examples of how @decorators work, and __call__ (able) objects? Decorators: http://personalpages.tds.net/~kent37/kk/1.htmlhttp://personalpages.tds.net/%7Ekent37/kk/1.html Kent ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] decorators, __call__ (able) objects
Can some one give, or point to some good examples of how @decorators work, and __call__ (able) objects? simple example of calling a class class myKlass(object): def __call__(self, *args, **kws): print i was called test = myKlass() test() i was called close. the example was right, but the description wasn't accurate... you meant, calling an instance. i'm going to plagarize and rip this right out of section 14.1.4 from Core Python Programming: Python provides the __call__() special method for classes, which allows a programmer to create objects (instances) that are callable. By default, the __call__() method is not implemented, meaning that most instances are not callable. However, if this method is overridden in a class definition, instances of such a class are made callable. Calling such instance objects is equivalent to invoking the __call__() method. Naturally, any arguments given in the instance call are passed as arguments to __call__(). as far as decorators go, kent's tutorial is great place to start. here are 2 more articles plus PEP 318, where they were defined: http://www.ibm.com/developerworks/linux/library/l-cpdecor.html http://www.artima.com/weblogs/viewpost.jsp?thread=240808 http://www.python.org/dev/peps/pep-0318 in addition, i devoted section 11.3.6 of Core Python to decorators. finally, it should be mentioned that starting in 2.6, you can now decorate *classes*, as seen here in PEP 3129: http://www.python.org/dev/peps/pep-3129/ hope this helps! -- wesley - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Core Python Programming, Prentice Hall, (c)2007,2001 Python Fundamentals, Prentice Hall, (c)2009 http://corepython.com wesley.j.chun :: wescpy-at-gmail.com python training and technical consulting cyberweb.consulting : silicon valley, ca http://cyberwebconsulting.com ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] decorators, __call__ (able) objects
agreed much better description, thanks On Wed, Jul 15, 2009 at 1:02 PM, wesley chun wes...@gmail.com wrote: Can some one give, or point to some good examples of how @decorators work, and __call__ (able) objects? simple example of calling a class class myKlass(object): def __call__(self, *args, **kws): print i was called test = myKlass() test() i was called close. the example was right, but the description wasn't accurate... you meant, calling an instance. i'm going to plagarize and rip this right out of section 14.1.4 from Core Python Programming: Python provides the __call__() special method for classes, which allows a programmer to create objects (instances) that are callable. By default, the __call__() method is not implemented, meaning that most instances are not callable. However, if this method is overridden in a class definition, instances of such a class are made callable. Calling such instance objects is equivalent to invoking the __call__() method. Naturally, any arguments given in the instance call are passed as arguments to __call__(). as far as decorators go, kent's tutorial is great place to start. here are 2 more articles plus PEP 318, where they were defined: http://www.ibm.com/developerworks/linux/library/l-cpdecor.html http://www.artima.com/weblogs/viewpost.jsp?thread=240808 http://www.python.org/dev/peps/pep-0318 in addition, i devoted section 11.3.6 of Core Python to decorators. finally, it should be mentioned that starting in 2.6, you can now decorate *classes*, as seen here in PEP 3129: http://www.python.org/dev/peps/pep-3129/ hope this helps! -- wesley - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Core Python Programming, Prentice Hall, (c)2007,2001 Python Fundamentals, Prentice Hall, (c)2009 http://corepython.com wesley.j.chun :: wescpy-at-gmail.com python training and technical consulting cyberweb.consulting : silicon valley, ca http://cyberwebconsulting.com ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] decorators, __call__ (able) objects
hi kent, thanks, i read through the link but still haven't got my head around this concept. will read on. cheers, t Original-Nachricht Datum: Wed, 15 Jul 2009 08:33:33 -0400 Von: Kent Johnson ken...@tds.net An: Todd Matsumoto tmatsum...@gmx.net CC: tutor@python.org Betreff: Re: [Tutor] decorators, __call__ (able) objects On Wed, Jul 15, 2009 at 7:41 AM, Todd Matsumototmatsum...@gmx.net wrote: Hi, Can some one give, or point to some good examples of how @decorators work, and __call__ (able) objects? Decorators: http://personalpages.tds.net/~kent37/kk/1.html Kent -- GRATIS für alle GMX-Mitglieder: Die maxdome Movie-FLAT! Jetzt freischalten unter http://portal.gmx.net/de/go/maxdome01 ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
