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How to get a complete list of object's methods and attributes?

...butes, the short answer is: no. The problem is that the attributes are actually defined as the arguments accepted by the getattr built-in function. As the user can reimplement __getattr__, suddenly allowing any kind of attribute, there is no possible generic way to generate that list. The dir functi...
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How to get number of entries in a Lua table?

...ual, any of 3, 5 and 9 are valid results for #t. According to the manual, calling # on non-sequences is undefined. That means that any result (-1, 3, 3.14, 5, 9) is valid. – cubuspl42 May 12 '14 at 20:08 ...
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Is there a simple, elegant way to define singletons? [duplicate]

... I don't really see the need, as a module with functions (and not a class) would serve well as a singleton. All its variables would be bound to the module, which could not be instantiated repeatedly anyway. If you do wish to use a cla...
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get current url in twig template?

...ttributes.get('_route_params')) %} The app global view variable contains all sorts of useful shortcuts, such as app.session and app.security.token.user, that reference the services you might use in a controller. share ...
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How to implement a binary tree?

...ice implementation. I'm just here to point out some style stuff. python usually does node is not None instead of your (node!=None). Also, you can use the __str__ function instead of the printTree method. – Jeff Mandell Oct 18 '15 at 2:30 ...
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Elasticsearch query to return all records

I have a small database in Elasticsearch and for testing purposes would like to pull all records back. I am attempting to use a URL of the form... ...
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Why do people use __(double underscore) so much in C++

...specific, and are slightly more detailed than some others have suggested. All identifiers that contain a double underscore or start with an underscore followed by an uppercase letter are reserved for the use of the implementation at all scopes, i.e. they might be used for macros. In addition, all ...
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How to avoid circular imports in Python? [duplicate]

....py Types of circular import problems Circular import dependencies typically fall into two categories depending on what you're trying to import and where you're using it inside each module. (And whether you're using python 2 or 3). 1. Errors importing modules with circular imports In some cases...
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Why use Abstract Base Classes in Python?

...emented classes. Long version There is a contract between a class and its callers. The class promises to do certain things and have certain properties. There are different levels to the contract. At a very low level, the contract might include the name of a method or its number of parameters. In a s...
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Differences between lodash and underscore [closed]

...h run in Node, Ringo, Rhino, Narwhal, PhantomJS, and browsers), better overall performance and optimizations for large arrays/object iteration, and more flexibility with custom builds and template pre-compilation utilities. Because Lo-Dash is updated more frequently than Underscore, a lodash unders...