magic-function

Problem Most iPython "magic functions" work fine for me right off the bat: %hist , %time , %prun , etc. However, I noticed that %lprun could not be found with iPython as I'd installed it originally. Attempt to Resolve I then discovered that I should install the line_profiler module. I have installed this module, but still cannot seem to get the magic function to work correctly. If I attempt to call %lprun , iPython still cannot find the function. If I call it with the full name ( line_profiler.magic_lprun ), the function can be found, but I cannot get it to work at all. Below is an example of

Possible Duplicate: Intercept operator lookup on metaclass How can I intercept calls to python’s “magic” methods in new style classes? Consider the following code: class ClassA(object): def __getattribute__(self, item): print 'custom__getattribute__ - ' + item return '' def __str__(self): print 'custom__str__' return '' a=ClassA() print 'a.__str__: ', a.__str__ print 'str(a): ', str(a) The output was surprising to me: a.__str__: custom__getattribute__ - __str__ str(a): custom__str__ Isn't str(a) supposed to be mapped to the magic method a.__str__() ? If I remove the custom ClassA.__str__() ,

In Mercurial, many of the extensions wrap their help/syntax string in a call to an underscore function, like so: _('[OPTION] [QUEUE]') This confuses me, because it does not seem necessary (the Writing Extensions instructions don't mention it) and there doesn't seem to be a _ defined in the class, so I'm wondering if this is some special syntax that I don't understand, perhaps another way to say lambda, or maybe the identity function? Additionally I'm wondering what the benefit of this methodology (whatever it is) is over just the raw string like the documentation suggests. Nothing I've seen in

The magic function __call() in php are used in classes. Are there any similar magic function but for functions instead? Like __autoload() is for functions. For example something like this function __call($name, $arguments) { echo "Function $name says {$arguments[0]} "; } random_func("hello"); Nope, I don't think such a magic function exists. One workaround for this would be to put your functions into a static class, and add a __callStatic magic method to that class (> PHP 5.3 only, I'm afraid): class Func { /** As of PHP 5.3.0 */ public static function __callStatic($name, $arguments) { // Note

A similar question discusses __construct , but I left it in my title for people searching who find this one. Apparently, __get and __set take a parameter that is the variable being gotten or set. However, you have to know the variable name (eg, know that the age of the person is $age instead of $myAge). So I don't see the point if you HAVE to know a variable name, especially if you are working with code that you aren't familiar with (such as a library). I found some pages that explain __get() , __set() , and __call() , but I still don't get why or when they are useful. This page will probably