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Difference between variable declaration syntaxes in Javascript (including global variables)?
...here are a couple of differences, though in practical terms they're not usually big ones.
There's a fourth way, and as of ES2015 (ES6) there's two more. I've added the fourth way at the end, but inserted the ES2015 ways after #1 (you'll see why), so we have:
var a = 0; // 1
let a = 0; // 1...
What are the differences between NP, NP-Complete and NP-Hard?
... the technical definitions require quite some time to understand. First of all, let's remember a preliminary needed concept to understand those definitions.
Decision problem: A problem with a yes or no answer.
Now, let us define those complexity classes.
P
P is a complexity class that repres...
How to unload a package without restarting R
...nt version and a stable version in different libraries). To guarantee that all copies are detached, use this function.
detach_package <- function(pkg, character.only = FALSE)
{
if(!character.only)
{
pkg <- deparse(substitute(pkg))
}
search_item <- paste("package", pkg, sep = ":...
How to concatenate twice with the C preprocessor and expand a macro as in “arg ## _ ## MACRO”?
...ssing token (see below), is
replaced by the corresponding argument after all macros contained therein have been
expanded. Before being substituted, each argument’s preprocessing tokens are
completely macro replaced as if they formed the rest of the preprocessing file; no other
preprocessin...
How to compile a static library in Linux?
...:
target: prerequisites - the rule head
$@ - means the target
$^ - means all prerequisites
$< - means just the first prerequisite
ar - a Linux tool to create, modify, and extract from archives see the man pages for further information. The options in this case mean:
r - replace files existing...
Types in MySQL: BigInt(20) vs Int(20)
...gInt , MediumInt , and Int are... it would seem obvious that they would allow for larger numbers; however, I can make an Int(20) or a BigInt(20) and that would make seem that it is not necessarily about size.
...
How to find the Windows version from the PowerShell command line
...C
System Locale : ru;Russian
Hotfix(s) : 274 Hotfix(s) Installed.,[01]: KB2849697,[02]: KB2849697,[03]:...
Windows 10 output for the same command:
OS Name : Microsoft Windows 10 Enterprise N 2016 LTSB
OS Version : 10.0.14393 N/A Build 14393
OS Manufacturer ...
If my interface must return Task what is the best way to have a no-operation implementation?
...mprove performance even more if you cache the already completed task since all instances of completed tasks are the same:
public static class TaskExtensions
{
public static readonly Task CompletedTask = Task.FromResult(false);
}
With TaskExtensions.CompletedTask you can use the same instance ...
Track the time a command takes in UNIX/LINUX?
...ts the Gnu time command, but time is a builtin in bash, which doesn't have all the options documented there.
– Ben Crowell
Jun 17 '17 at 15:27
add a comment
...
Convert int to string?
...compile time, but it wouldn't even raise a runtime exception it would just allow bad data.
– Timothy Gonzalez
Dec 15 '16 at 16:29
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