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Declaring variables inside loops, good practice or bad practice?
...se, you may need to initialize it every time. You can also create a larger block, encompassing the loop, whose sole purpose is to declare variables which must retain their value from one loop to another. This typically includes the loop counter itself.
{
int i, retainValue;
for (i=0; i<N...
Ruby, Difference between exec, system and %x() or Backticks
... This is not so simple. In my case it "was OK (and need) to block until the process complete" to then use popen3 to check the STDOUT/STDERR outputs.
– Nakilon
Sep 25 '16 at 3:06
...
trying to align html button at the center of the my page [duplicate]
...ut using text-align on the parent div by simple using margin:auto; display:block;
For example:
HTML
<div>
<button>Submit</button>
</div>
CSS
button {
margin:auto;
display:block;
}
SEE IT IN ACTION: CodePen
...
Do zombies exist … in .NET?
...either using a lock statement instead, or putting the release in a finally block.
See also
Subtleties of C# IL
codegen
for a very subtle case where an exception can prevent a lock from
being released even when using the lock keyword (but only in .Net 3.5 and earlier)
Locks and exceptions do not
m...
Simulate CREATE DATABASE IF NOT EXISTS for PostgreSQL?
...ment. The manual:
CREATE DATABASE cannot be executed inside a transaction block.
So it cannot be run directly inside a function or DO statement, where it would be inside a transaction block implicitly.
(SQL procedures, introduced with Postgres 11, cannot help with this either.)
Workaround from wit...
Where is Erlang used and why? [closed]
...ng shines.
handle many connections
It is very easy to build scalable non-blocking TCP/IP servers with erlang. In fact, it was designed to solve this problem.
And given it can spawn hundreds of thousand of processes (and not threads, it's a share-nothing approach, which is simpler to design), ejabb...
Is there a vr (vertical rule) in html?
...ment can be used to separate items vertically (anything you set to display:block and float:left with any height set)
– Andy Baird
Aug 4 '09 at 17:09
20
...
Why not use exceptions as regular flow of control?
...iew (I'm pretty sure the perfomance overhead is minimal). I don't like try-blocks all over the place.
Take this example:
try
{
DoSomeMethod(); //Can throw Exception1
DoSomeOtherMethod(); //Can throw Exception1 and Exception2
}
catch(Exception1)
{
//Okay something messed up, but is it So...
Sending an HTTP POST request on iOS
...ing : Any]
//create the url with URL
let url = URL(string: "www.requestURL.php")! //change the url
//create the session object
let session = URLSession.shared
//now create the URLRequest object using the url object
var request = URLRequest(url: url)
request.httpMethod = "POST" //set http method as P...
The program can't start because libgcc_s_dw2-1.dll is missing
I have created a simple program in C++ with Code::Blocks.
16 Answers
16
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