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Delete/Reset all entries in Core Data?
Do you know of any way to delete all of the entries stored in Core Data? My schema should stay the same; I just want to reset it to blank.
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How update the _id of one MongoDB Document?
I want update an _id field of one document. I know it's not a really good pratice. But with some technical reason, I need update it. If I try to update it I get:
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How to ignore user's time zone and force Date() use specific time zone
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A Date object's underlying value is actually in UTC. To prove this, notice that if you type new Date(0) you'll see something like: Wed Dec 31 1969 16:00:00 GMT-0800 (PST). 0 is treated as 0 in GMT, but .toString() method shows the local time.
Big note, UTC stands ...
Using a dispatch_once singleton model in Swift
...variables), and is thread safe by the definition of let. This is now officially recommended way to instantiate a singleton.
Class constants were introduced in Swift 1.2. If you need to support an earlier version of Swift, use the nested struct approach below or a global constant.
Nested struct
cl...
Convert PDF to clean SVG? [closed]
...t they often lose the font data, but don't seem to approximate a good, installed font. How does PDF display it if SVG can't?
– DanRedux
Apr 23 '12 at 21:30
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Django templates: verbose version of a choice
... (universal), though - unless you know a way to iterate in a template over all get_FOO_display methods of a model object :) I'm a bit too lazy for writing non-generic templates ;) Moreover, the docs say it's a model instance's method. Therefore it'd have to be a model form bound to an existing obj...
How to identify if the DLL is Debug or Release build (in .NET) [duplicate]
...s to check the compiled assemblies itself. There is this very useful tool called '.NET Assembly Information' found here by Rotem Bloom. After you install this, it associates itself with .dll files to open with itself. After installing you can just double-click on the Assembly to open and it will giv...
How to use/install gcc on Mac OS X 10.8 / Xcode 4.4
... SDK frameworks and
headers. Many useful tools are included, such as the Apple LLVM
compiler, linker, and Make. If you use Xcode, these tools are also
embedded within the Xcode IDE, and can be installed on your system
using the Downloads preferences pane within Xcode 4.3 and later. This
p...
How to write WinForms code that auto-scales to system font and dpi settings?
...h to WPF." However, I think that is based on .NET 1.1; it appears they actually did a pretty good job of implementing auto-scaling in .NET 2.0. At least based on our research and testing so far. However, if some of you out there know better, we'd love to hear from you. (Please don't bother arguing ...
Example for boost shared_mutex (multiple reads/one write)?
I have a multithreaded app that has to read some data often, and occasionally that data is updated. Right now a mutex keeps access to that data safe, but it's expensive because I would like multiple threads to be able to read simultaneously, and only lock them out when an update is needed (the updat...