I don’t think there’s anything deeper going on than what you have originally said: it’s just syntactic sugar whereby the compiler converts f(a) into f.apply(a) as a special syntax case. This might seem like a specific rule, but only a few of these (for example, with update) allows for DSL-like constructs and libraries.
[UPDATE] – added (yet another) explanation on for comprehensions The * method: This returns the default projection – which is how you describe: ‘all the columns (or computed values) I am usually interested’ in. Your table could have several fields; you only need a subset for your default projection. The default projection must match the … Read more
__get, __set, __call and __callStatic are invoked when the method or property is inaccessible. Your $bar is public and therefor not inaccessible. See the section on Property Overloading in the manual: __set() is run when writing data to inaccessible properties. __get() is utilized for reading data from inaccessible properties. The magic methods are not substitutes … Read more
Use class-level PHPDoc comment — specifically @method tag — works fine in PhpStorm: /** * @method static someClass get_by_user_id(int $id) Bla-bla * @method static someClass get_first_by_id(int $id) */ abstract class a { … In the above: @method — PHPDoc tag static — tells that this is static method someClass or $this — return type get_by_user_id … Read more
How do they achieve internally that you are able to pass something like x > 5 into a method? The short answer is that they don’t. Any sort of logical operation on a numpy array returns a boolean array. (i.e. __gt__, __lt__, etc all return boolean arrays where the given condition is true). E.g. x … Read more
First of all A.__dict__.__dict__ is different from A.__dict__[‘__dict__’]. The former doesn’t exist and the latter is the __dict__ attribute that the instances of the class would have. It’s a data descriptor object that returns the internal dictionary of attributes for the specific instance. In short, the __dict__ attribute of an object can’t be stored in … Read more
The way you describe it is absolutely not possible. Assignment to a name is a fundamental feature of Python and no hooks have been provided to change its behavior. However, assignment to a member in a class instance can be controlled as you want, by overriding .__setattr__(). class MyClass(object): def __init__(self, x): self.x = x … Read more
AFAIK, len is special in this respect and has historical roots. Here’s a quote from the FAQ: Why does Python use methods for some functionality (e.g. list.index()) but functions for other (e.g. len(list))? The major reason is history. Functions were used for those operations that were generic for a group of types and which were … Read more
I almost posted this as a comment to the other answers but it’s really an answer in and of itself. To make your items sortable, they only need to implement __lt__. That’s the only method used by the built in sort. The other comparisons or functools.total_ordering are only needed if you actually want to use … Read more
I have been exactly in your case in the past. And I went for magic methods. This was a mistake, the last part of your question says it all : this is slower (than getters/setters) there is no auto-completion (and this is a major problem actually), and type management by the IDE for refactoring and … Read more