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Swift: Testing optionals for nil
...let
guard let can do similar things. It's main purpose is to make it logically more reasonable. It's like saying Make sure the variable is not nil, otherwise stop the function. guard let can also do extra condition checking as if let.
The differences are that the unwrapped value will be available ...
Is It Possible to NSLog C Structs (Like CGRect or CGPoint)?
... With AppKit on OS X you would need to convert to an NSPoint and then call NSStringFromPoint. For example: NSStringFromPoint(NSPointFromCGPoint(point))
– Alex
Aug 22 '12 at 17:56
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Limiting floats to two decimal points
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You are running into the old problem with floating point numbers that not all numbers can be represented exactly. The command line is just showing you the full floating point form from memory.
With floating point representation, your rounded version is the same number. Since computers are binary, ...
Is there a standard for storing normalized phone numbers in a database?
...s flexible enough to handle international numbers, and also something that allows the various parts of the number to be queried efficiently.
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error LNK2019: 无法解析的外部符号_socket，该符号在函数 中被引用 - C/C+...
error LNK2019: 无法解析的外部符号_socket，该符号在函数 中被引用1>NetClient.obj : error LNK2019: 无法解析的外部符号 _closesocket@4，该符号在函数 _main 中被引用1>NetClient.obj : error L...1>NetClient.obj : error LNK2019: 无法解析的外部符号 _closesocket@...
Internet Explorer 11 disable “display intranet sites in compatibility view” via meta tag not working
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This problem is generally caused by the website/intranet URL being placed in one of:
Compatibility Mode List
Internet Explorer Intranet Zone
(with Display intranet sites in Compatibility View setting enabled)
Enterprise Mode List
On corporate...
Position a CSS background image x pixels from the right?
...ected as the "Correct answer". According to MDN it's supported in IE9+ and all other browsers, which is great! developer.mozilla.org/en-US/docs/Web/CSS/…
– fregante
Sep 27 '13 at 0:16
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How do I make calls to a REST api using C#?
...and this thread is one of the top results when doing a Google search for "call restful service c#".
Current guidance from Microsoft is to use the Microsoft ASP.NET Web API Client Libraries to consume a RESTful service. This is available as a NuGet package, Microsoft.AspNet.WebApi.Client. You will n...
How can you profile a Python script?
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Python includes a profiler called cProfile. It not only gives the total running time, but also times each function separately, and tells you how many times each function was called, making it easy to determine where you should make optimizations.
You c...
What is a memory fence?
...ead/writes occur in the order you expect. For example a 'full fence' means all read/writes before the fence are comitted before those after the fence.
Note memory fences are a hardware concept. In higher level languages we are used to dealing with mutexes and semaphores - these may well be implemen...