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Is the practice of returning a C++ reference variable evil?
...const&", what actually happens is that the return statement implicitly converts the temp, which is of type T, to type "T const&" as per 6.6.3.2 (a legal conversion but one which does not extend lifetime), and then the calling code initialises the ref of type "T const&" with the function'...
T-SQL datetime rounded to nearest minute and nearest hours with using functions
...
DECLARE @date As DateTime2
SET @date = '2007-09-22 15:07:38.850'
SELECT CONVERT(VARCHAR(16), @date, 120) --2007-09-22 15:07
SELECT CONVERT(VARCHAR(13), @date, 120) --2007-09-22 15
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improv...
How To Check If A Key in **kwargs Exists?
...to you in advance. However, if they are, here is a simple example:
import sys
def myfunc(**kwargs):
args = {'country':'England','town':'London',
'currency':'Pound', 'language':'English'}
diff = set(kwargs.keys()) - set(args.keys())
if diff:
print("Invalid args:",tu...
What happens when a computer program runs?
...lso note, these aren't actual lines of C code executing. The compiler has converted them into machine language instructions in your executable. They are then (generally) copied from the TEXT area into the CPU pipeline, then into the CPU registers, and executed from there. [This was incorrect. Se...
Fast way to get image dimensions (not filesize)
...ng 20-60 KB read by "identify" for 5-335 MB images (I also tested against "convert" which showed all bytes being read). So it looks like "identify" is a good choice here (since it supports all popular formats and reads just the header).
– coderforlife
Feb 12 '1...
Check if an apt-get package is installed and then install it if it's not on Linux
I'm working on a Ubuntu system and currently this is what I'm doing:
22 Answers
22
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How can I calculate the difference between two dates?
...s of time, they do not have any associated time-zone information. When you convert a string to a date using e.g. an NSDateFormatter, the NSDateFormatter converts the time from the configured timezone. Therefore, the number of seconds between two NSDate objects will always be time-zone-agnostic.
Fur...
What is a JavaBean exactly?
...s to (and implies that it is capable of) "serialization" -- a process that converts an instance into a stream of bytes. Those bytes can be stored in files, sent over a network connection, etc, and have enough info to allow a JVM (at least, one that knows about the object's type) to reconstruct the ...
Java 8 stream reverse order
...t;Integer> list = Arrays.asList(1,2,3,4);
list.stream()
.boxed() // Converts Intstream to Stream<Integer>
.sorted(Collections.reverseOrder()) // Method on Stream<Integer>
.forEach(System.out::println);
...
How do I provide custom cast support for my class?
... implicit operator byte[] (MyType x)
{
byte[] ba = // put code here to convert x into a byte[]
return ba;
}
or
public static explicit operator MyType(byte[] x)
{
if (!CanConvert)
throw new DataValueNullException();
// Factory to convert byte[] x into MyType
MyType mt ...