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SQLite error 'attempt to write a readonly database' during insert?
... Also, SELinux (if installed) must not be enforcing. Took me a day and a half to figure that one out.
– Steve V.
Dec 19 '10 at 8:31
1
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Is there a way to measure how sorted a list is?
...Formally, let A(1), A(2), ..., A(n) be a sequence of n numbers.If i < j and A(i) > A(j), then the pair (i,j) is called an inversion of A.
The inversion number of a sequence is one common measure of its sortedness.Formally, the inversion number is defined to be the number of inversions, that is...
Python constructors and __init__
Why are constructors indeed called "Constructors"? What is their purpose and how are they different from methods in a class?
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PHP: How to send HTTP response code?
...
I just found this question and thought it needs a more comprehensive answer:
As of PHP 5.4 there are three methods to accomplish this:
Assembling the response code on your own (PHP >= 4.0)
The header() function has a special use-case that detects...
What are 'closures' in .NET?
...
The general feature of closures is implemented in C# by anonymous methods and lambda expressions.
Here's an example using an anonymous method:
using System;
class Test
{
static void Main()
{
Action action = CreateAction();
action();
action();
}
static Act...
Android: How to enable/disable option menu item on button click?
...enu() method is called
only once, as described above. The
system keeps and re-uses the Menu you
define in this method until your
activity is destroyed. If you want to
change the Options Menu any time after
it's first created, you must override
the onPrepareOptionsMenu() method.
This ...
What character encoding should I use for a HTTP header?
...e http://html5boilerplate.com/ for more info) for a Server HTTP-header and am wondering if it is "allowed" per spec.
2 ...
How to add custom validation to an AngularJS form?
I have a form with input fields and validation setup by adding the required attributes and such. But for some fields I need to do some extra validation. How would I "tap in" to the validation that FormController controls?
...
passing several arguments to FUN of lapply (and others *apply)
...n the lapply call as an argument, like so:
lapply(input, myfun, arg1=6)
and lapply, recognizing that arg1 is not an argument it knows what to do with, will automatically pass it on to myfun. All the other apply functions can do the same thing.
An addendum: You can use ... when you're writing you...
What's the difference between std::move and std::forward
...
std::move takes an object and allows you to treat it as a temporary (an rvalue). Although it isn't a semantic requirement, typically a function accepting a reference to an rvalue will invalidate it. When you see std::move, it indicates that the value ...