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Get object by id()? [duplicate]

...The Python weakref module lets you keep references, dictionary references, and proxies to objects without having those references count in the reference counter. They're like symbolic links. share | ...
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Mathematical functions in Swift

...an import only Darwin. import Darwin If you want mathematical functions and other standard classes and functions. You can import Foundation. import Foundation If you want everything and also classes for user interface, it depends if your playground is for OS X or iOS. For OS X, you need impor...
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How to pass arguments to a Button command in Tkinter?

...sonally prefer to use lambdas in such a scenario, because imo it's clearer and simpler and also doesn't force you to write lots of wrapper methods if you don't have control over the called method, but that's certainly a matter of taste. That's how you'd do it with a lambda (note there's also some i...
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How to check if AlarmManager already has an alarm set?

...o check if a particular alarm (registered via AlarmManager) is already set and running. Results from google seem to indicate that there is no way to do this. Is this still correct? I need to do this check in order to advise the user before any action is taken to create a new alarm. ...
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List of lists changes reflected across sublists unexpectedly

...(3)] which will reevaluate [1]*4 each time instead of evaluating it once and making 3 references to 1 list. You might wonder why * can't make independent objects the way the list comprehension does. That's because the multiplication operator * operates on objects, without seeing expressions. Wh...
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Suppressing deprecated warnings in Xcode

With all the SDKs floating around, it's handy to be able to build for multiple SDKs and platforms. However, bouncing from 3.2 to 3.0 and even occasionally 2.x, I frequently get deprecated warnings involving methods that have changed or been superseded: ...
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How to manually set an authenticated user in Spring Security / SpringMVC

.... This code is used within a Spring Webflow flow, hence the RequestContext and ExternalContext classes. But the part that is most relevant to you is the doAutoLogin method. public String registerUser(UserRegistrationFormBean userRegistrationFormBean, RequestContext reque...
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How to fix: “UnicodeDecodeError: 'ascii' codec can't decode byte”

...ing that does not contain any encoding. They only hold Unicode point codes and therefore can hold any Unicode point from across the entire spectrum. Strings contain encoded text, beit UTF-8, UTF-16, ISO-8895-1, GBK, Big5 etc. Strings are decoded to Unicode and Unicodes are encoded to strings. Files ...
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Wrap a delegate in an IEqualityComparer

...inverse is true. In short, @Dan Tao is completely correct in what he says, and this answer is simply the application of this fact to a previously incomplete answer – Ruben Bartelink Dec 20 '10 at 5:10 ...
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how to emulate “insert ignore” and “on duplicate key update” (sql merge) with postgresql?

...m a subquery, you're best of splitting it into two queries, one for INSERT and one for UPDATE (as an appropriate join/subselect of course - no need to write your main filter twice) share | improve t...