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Controlling the screenshot in the iOS 7 multitasking switcher
...cher in iOS 7 and especially the screenshot that the OS takes when the app is going into hibernation.
8 Answers
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Why does Python use 'magic methods'?
...n playing around with Python recently, and one thing I'm finding a bit odd is the extensive use of 'magic methods', e.g. to make its length available, an object implements a method, def __len__(self) , and then it is called when you write len(obj) .
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How to output something in PowerShell
... file. The script fetches a web page and checks whether the page's content is the string "OK".
7 Answers
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Java: Multiple class declarations in one file
...le top level classes in a single file, providing that at most one of these is public (see JLS §7.6 ). See below for example.
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LIMIT 10..20 in SQL Server
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The LIMIT clause is not part of standard SQL. It's supported as a vendor extension to SQL by MySQL, PostgreSQL, and SQLite.
Other brands of database may have similar features (e.g. TOP in Microsoft SQL Server), but these don't always work...
When and why JPA entities should implement Serializable interface?
The question is in the title. Below I just described some of my thoughts and findings.
14 Answers
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When to call activity context OR application context?
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getApplicationContext() is almost always wrong. Ms. Hackborn (among others) have been very explicit that you only use getApplicationContext() when you know why you are using getApplicationContext() and only when you need to use getApplicationContext...
Is there a decorator to simply cache function return values?
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Starting from Python 3.2 there is a built-in decorator:
@functools.lru_cache(maxsize=100, typed=False)
Decorator to wrap a function with a memoizing callable that saves up to the maxsize most recent calls. It can save time when an expensive or I/O bound...
What is the best way to convert an array to a hash in Ruby
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NOTE: For a concise and efficient solution, please see Marc-André Lafortune's answer below.
This answer was originally offered as an alternative to approaches using flatten, which were the most highly upvoted at the time of writing. I shou...
Filtering for empty or NULL names in a queryset
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You could do this:
Name.objects.exclude(alias__isnull=True)
If you need to exclude null values and empty strings, the preferred way to do so is to chain together the conditions like so:
Name.objects.exclude(alias__isnull=True).exclude(a...