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What is “stdafx.h” used for in Visual Studio?
A file named stdafx.h is automatically generated when I start a project in Visual Studio 2010. I need to make a cross-platform C++ library, so I don't/can't use this header file.
...
What is an “unwrapped value” in Swift?
...st, you have to understand what an Optional type is. An optional type basically means that the variable can be nil.
Example:
var canBeNil : Int? = 4
canBeNil = nil
The question mark indicates the fact that canBeNil can be nil.
This would not work:
var cantBeNil : Int = 4
cantBeNil = nil // can...
Is it better to use C void arguments “void foo(void)” or not “void foo()”? [duplicate]
...either the count is communicated nor the types of what is needed - as with all function declarations that use identifier lists. So the caller has to know the types and the count precisely before-hand. So if the caller calls the function giving it some argument, the behavior is undefined. The stack c...
Cannot set content-type to 'application/json' in jQuery.ajax
...S header is used to find out if the request from the originating domain is allowed. Using fiddler, I added the following to the response headers from my server.
Access-Control-Allow-Origin: *
Access-Control-Allow-Headers: Content-Type
Access-Control-Allow-Methods: POST, GET, OPTIONS
Once the b...
Convert UTC to local time in Rails 3
...mes. See them with:
rake time:zones:us
You can also run rake time:zones:all for all time zones.
To see more zone-related rake tasks: rake -D time
So, to convert to EST, catering for DST automatically:
Time.now.in_time_zone("Eastern Time (US & Canada)")
...
Automatically deleting related rows in Laravel (Eloquent ORM)
...();
static::deleting(function($user) { // before delete() method call this
$user->photos()->delete();
// do the rest of the cleanup...
});
}
}
You should probably also put the whole thing inside a transaction, to ensure the referential integrity...
Are the days of passing const std::string & as a parameter over?
...he said is because of cases like this.
Let's say I have function A which calls function B, which calls function C. And A passes a string through B and into C. A does not know or care about C; all A knows about is B. That is, C is an implementation detail of B.
Let's say that A is defined as follow...
Is there a replacement for unistd.h for Windows (Visual C)?
...nsole program written for Unix to the Windows platform ( Visual C++ 8.0 ). All the source files include "unistd.h", which doesn't exist. Removing it, I get complaints about misssing prototypes for 'srandom', 'random', and 'getopt'.
I know I can replace the random functions, and I'm pretty sure I ca...
Read Excel File in Python
...value))
except ValueError:
pass
finally:
values.append(value)
item = Arm(*values)
items.append(item)
for item in items:
print item
print("Accessing one single value (eg. DSPName): {0}".format(item.dsp_name))
print
...
How to install packages using pip according to the requirements.txt file from a local directory?
...
This works for me:
$ pip install -r requirements.txt --no-index --find-links file:///tmp/packages
--no-index - Ignore package index (only looking at --find-links URLs instead).
-f, --find-links <URL> - If a URL or path to an html file, then par...