Re: dynamic invoke
Sushant napisał(a): getattr seems to be converting string into function pointer and I am just saying that string cannot be used as a function pointer in Python as may be in PHP. It seems, but it does not. Getattr performs lookup on object's attributes dict, it does not convert anything. The abstraction of function pointer is also wrong here, it's a reference to an object (any object, not just function). The result might seems similar, but works quite differently. -- Jarek Zgoda Skype: jzgoda | GTalk: [EMAIL PROTECTED] | voice: +48228430101 We read Knuth so you don't have to. (Tim Peters) -- http://mail.python.org/mailman/listinfo/python-list
Re: dynamic invoke
On Oct 19, 6:34 am, Nils [EMAIL PROTECTED] wrote: Use apply(): http://docs.python.org/lib/non-essential-built-in-funcs.html Did you actually read the title of the page you linked to (Non- essential Built-in Functions)? -- http://mail.python.org/mailman/listinfo/python-list
dynamic invoke
Hello, Is there any way (other then eval) to invoke a method by passing method name in a string. It's very simple in php: $oFoo = new Foo(); $dynamiMethod = bar; $oFoo-$dynamiMethod(); Unfortunately I can't find a good solution to do the same thing in python. Does it have some build-in function to do it? Kind Regards, Lukasz. -- http://mail.python.org/mailman/listinfo/python-list
Re: dynamic invoke
[EMAIL PROTECTED] wrote: On 19 Oct, 11:45, Jarek Zgoda [EMAIL PROTECTED] wrote: [EMAIL PROTECTED] napisa³(a): Is there any way (other then eval) to invoke a method by passing method name in a string. It's very simple in php: $oFoo = new Foo(); $dynamiMethod = bar; $oFoo-$dynamiMethod(); Unfortunately I can't find a good solution to do the same thing in python. Does it have some build-in function to do it? foo = getattr(module_or_object, 'function_name') foo() -- Jarek Zgoda Skype: jzgoda | GTalk: [EMAIL PROTECTED] | voice: +48228430101 We read Knuth so you don't have to. (Tim Peters) Superb! I was lookig for something like this. Belive me or not but i spent lots of time looking for this simple solution :) The above clearly is a solution to your problem. I just wonder if you _need_ it. PHP doesn't have the concept of a function reference. So you need to store/use names. But in Python you can do this: def foo(): print foo callback = foo callback() As trivial this code is, it illustrates one thing: passing around functions is as easy as passing around other values. So maybe you don't need a function name. Only a suggestion to ponder about though, it might be that your usecase is not suited for the above. Diez -- http://mail.python.org/mailman/listinfo/python-list
Re: dynamic invoke
I did not know about getattr and it is the right thing. getattr seems to be converting string into function pointer and I am just saying that string cannot be used as a function pointer in Python as may be in PHP. I copied the PHP code so I did not replace arrow with dot. Good point :) -Sushant. On Friday 19 October 2007 11:05 am, Diez B. Roggisch wrote: Sushant wrote: Python will not allow string to be used a function pointer. It is type unsafe. Best way is to convert string into function pointers manually. if dynamicMethod == 'bar': method = oFoo-bar else: method = oFoo-default method() Sorry to say so, but that answer is bogus. It's not even Python! Jarek has already shown how to solve this problem. And type-safety-issues have nothing to do with it at all. Diez -- http://mail.python.org/mailman/listinfo/python-list
Re: dynamic invoke
On Fri, 19 Oct 2007 11:34:39 +, Nils wrote: Use apply(): http://docs.python.org/lib/non-essential-built-in-funcs.html No, don't use apply. Not only does it not solve the original poster's problem, it is a deprecated function. You shouldn't use it in new code. -- Steven. -- http://mail.python.org/mailman/listinfo/python-list
Re: dynamic invoke
Sushant wrote: Python will not allow string to be used a function pointer. It is type unsafe. Best way is to convert string into function pointers manually. if dynamicMethod == 'bar': method = oFoo-bar else: method = oFoo-default method() Sorry to say so, but that answer is bogus. It's not even Python! Jarek has already shown how to solve this problem. And type-safety-issues have nothing to do with it at all. Diez -- http://mail.python.org/mailman/listinfo/python-list
Re: dynamic invoke
Python will not allow string to be used a function pointer. It is type unsafe. Best way is to convert string into function pointers manually. if dynamicMethod == 'bar': method = oFoo-bar else: method = oFoo-default method() On Friday 19 October 2007 7:56 am, Diez B. Roggisch wrote: Nils wrote: On Oct 19, 12:39 pm, [EMAIL PROTECTED] wrote: Hello, Is there any way (other then eval) to invoke a method by passing method name in a string. It's very simple in php: $oFoo = new Foo(); $dynamiMethod = bar; $oFoo-$dynamiMethod(); Unfortunately I can't find a good solution to do the same thing in python. Does it have some build-in function to do it? Kind Regards, Lukasz. Use apply(): http://docs.python.org/lib/non-essential-built-in-funcs.html Apply doesn't help the OP - it's useful if you already have a function pointer. And it's obsoleted by the * and ** parameter passing mechanism. Diez -- http://mail.python.org/mailman/listinfo/python-list
Re: dynamic invoke
Nils wrote: On Oct 19, 12:39 pm, [EMAIL PROTECTED] wrote: Hello, Is there any way (other then eval) to invoke a method by passing method name in a string. It's very simple in php: $oFoo = new Foo(); $dynamiMethod = bar; $oFoo-$dynamiMethod(); Unfortunately I can't find a good solution to do the same thing in python. Does it have some build-in function to do it? Kind Regards, Lukasz. Use apply(): http://docs.python.org/lib/non-essential-built-in-funcs.html Apply doesn't help the OP - it's useful if you already have a function pointer. And it's obsoleted by the * and ** parameter passing mechanism. Diez -- http://mail.python.org/mailman/listinfo/python-list
Re: dynamic invoke
On Oct 19, 12:39 pm, [EMAIL PROTECTED] wrote: Hello, Is there any way (other then eval) to invoke a method by passing method name in a string. It's very simple in php: $oFoo = new Foo(); $dynamiMethod = bar; $oFoo-$dynamiMethod(); Unfortunately I can't find a good solution to do the same thing in python. Does it have some build-in function to do it? Kind Regards, Lukasz. Use apply(): http://docs.python.org/lib/non-essential-built-in-funcs.html Nils -- http://mail.python.org/mailman/listinfo/python-list
Re: dynamic invoke
[EMAIL PROTECTED] napisał(a): Is there any way (other then eval) to invoke a method by passing method name in a string. It's very simple in php: $oFoo = new Foo(); $dynamiMethod = bar; $oFoo-$dynamiMethod(); Unfortunately I can't find a good solution to do the same thing in python. Does it have some build-in function to do it? foo = getattr(module_or_object, 'function_name') foo() -- Jarek Zgoda Skype: jzgoda | GTalk: [EMAIL PROTECTED] | voice: +48228430101 We read Knuth so you don't have to. (Tim Peters) -- http://mail.python.org/mailman/listinfo/python-list
Re: dynamic invoke
On Fri, 19 Oct 2007 10:29:12 -0400, Sushant wrote: Python will not allow string to be used a function pointer. It is type unsafe. Best way is to convert string into function pointers manually. if dynamicMethod == 'bar': method = oFoo-bar else: method = oFoo-default method() I don't know what language you're programming in there, but it isn't Python. method = oFoo-bar ^ SyntaxError: invalid syntax -- Steven. -- http://mail.python.org/mailman/listinfo/python-list
Re: dynamic invoke
On 19 Oct, 11:45, Jarek Zgoda [EMAIL PROTECTED] wrote: [EMAIL PROTECTED] napisa³(a): Is there any way (other then eval) to invoke a method by passing method name in a string. It's very simple in php: $oFoo = new Foo(); $dynamiMethod = bar; $oFoo-$dynamiMethod(); Unfortunately I can't find a good solution to do the same thing in python. Does it have some build-in function to do it? foo = getattr(module_or_object, 'function_name') foo() -- Jarek Zgoda Skype: jzgoda | GTalk: [EMAIL PROTECTED] | voice: +48228430101 We read Knuth so you don't have to. (Tim Peters) Superb! I was lookig for something like this. Belive me or not but i spent lots of time looking for this simple solution :) Cheers. -- http://mail.python.org/mailman/listinfo/python-list
