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Threading in a PyQt application: Use Qt threads or Python threads?
I'm writing a GUI application that regularly retrieves data through a web connection. Since this retrieval takes a while, this causes the UI to be unresponsive during the retrieval process (it cannot be split into smaller parts). This is why I'd like to outsource the web connection to a separate wor...
Can't execute jar- file: “no main manifest attribute”
I have installed an application, when I try to run it (it's an executable jar) nothing happens. When I run it from the commandline with:
...
Check number of arguments passed to a Bash script
...ust like any other simple command, [ ... ] or test requires spaces between its arguments.
if [ "$#" -ne 1 ]; then
echo "Illegal number of parameters"
fi
Or
if test "$#" -ne 1; then
echo "Illegal number of parameters"
fi
Suggestions
When in Bash, prefer using [[ ]] instead as it doesn't do ...
Good tool to visualise database schema? [closed]
...d tools for visualising a pre-existing database schema? I'm using MySQL if it matters.
20 Answers
...
Visual Studio “Could not copy” … during build
...lar error messages in Visual Studio 2013.
Mostly, I have found that this situation has occurred when a debug process was halted because of an exception.
When clean+build has not resolved this problem for me, I have had success by doing the following:
Closing Visual Studio
Deleting the bin and ob...
When to use self over $this?
...atic_member;
}
}
new X();
?>
Here is an example of polymorphism with $this for member functions:
<?php
class X {
function foo() {
echo 'X::foo()';
}
function bar() {
$this->foo();
}
}
class Y extends X {
function foo() {
echo 'Y::foo()';...
Why does this go into an infinite loop?
... of illustration, since C# allows you to pass int parameters by reference with the ref keyword. I've decided to update it with actual legal Java code using the first MutableInt class I found on Google to sort of approximate what ref does in C#. I can't really tell if that helps or hurts the answer. ...
How using try catch for exception handling is best practice
...cation.ThreadException event, then decide :
For a UI application: to pop it to the user with an apology message (winforms)
For a Service or a Console application: log it to a file (service or console)
Then I always enclose every piece of code that is run externally in try/catch :
All events f...
When should I use git pull --rebase?
I know of some people who use git pull --rebase by default and others who insist never to use it. I believe I understand the difference between merging and rebasing, but I'm trying to put this in the context of git pull . Is it just about not wanting to see lots of merge commit messages, or are...
What's the difference between passing by reference vs. passing by value?
...wer meaning than the general term "reference" (because the phrase predates it).
Now, the authentic definition is:
When a parameter is passed by reference, the caller and the callee use the same variable for the parameter. If the callee modifies the parameter variable, the effect is visible to t...