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Output to the same line overwriting previous output?
...o need to import the sys module for this sort of simple usage. print() actually has a number of keyword arguments which can be used to greatly simplify code.
To use the same code on Python 2.6+, put the following line at the top of the file:
from __future__ import print_function
...
Why does z-index not work?
...ts have hierarchy, and each stacking context is considered in the stacking order of the parent's stacking context.
So with following html
div { border: 2px solid #000; width: 100px; height: 30px; margin: 10px; position: relative; background-color: #FFF; }
#el3 { background-color: #F0F; width:...
SetUnhandledExceptionFilter and the C/C++ Runtime Library - C/C++ - 清...
... in time (JIT) debugger if such a debugger is installed on the system.
In order to test the code, we will simulate a null pointer invalid access like this:
int main()
{
::SetUnhandledExceptionFilter(OurCrashHandler);
std::cout << "Normal null pointer crash" << std::endl;
char...
How to create a file in memory for user to download, but not through server?
.... If you have a text or CSV file, start the string with '\ufeff', the Byte Order Mark for UTF-16BE, and text editors will be able to read non-ASCII characters correctly.
– larspars
Nov 19 '14 at 9:06
...
Sort NSArray of date strings or objects
...s @selector(compare:) as the parameter. The -[NSDate compare:] method will order dates in ascending order for you. This is simpler than creating an NSSortDescriptor, and much simpler than writing your own comparison function. (NSDate objects know how to compare themselves to each other at least as e...
How do I perform the SQL Join equivalent in MongoDB?
...rect. The new $lookup operator added to the aggregation pipeline is essentially identical to a left outer join:
https://docs.mongodb.org/master/reference/operator/aggregation/lookup/#pipe._S_lookup
From the docs:
{
$lookup:
{
from: <collection to join>,
localField: <...
Is there a performance difference between a for loop and a for-each loop?
... iterator or index variable
completely. The resulting idiom
applies equally to collections and
arrays:
// The preferred idiom for iterating over collections and arrays
for (Element e : elements) {
doSomething(e);
}
When you see the colon (:), read it as
“in.” Thus, the loop ab...
Check if a class has a member function of a given signature
...oid ReportMemUsage(const TMap& m, std::true_type)
{
// We may call used_memory() on m here.
}
template<typename TMap>
void ReportMemUsage(const TMap&, std::false_type)
{
}
template<typename TMap>
void ReportMemUsage(const TMap& m)
{
ReportMemUsage(m,
std:...
How to convert vector to array
...making a pointer that points to the actual array the vector is using internally. If you want to copy GMan's answer explains how
– Michael Mrozek
May 27 '10 at 17:22
4
...
Comparing strings with == which are declared final in Java
...nal and initialized with a compile-time constant expression (§15.28), is called a constant variable.
Also from JLS §15.28 - Constant Expression:
Compile-time constant expressions of type String are always "interned" so as to share unique instances, using the method String#intern().
This ...