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Example for sync.WaitGroup correct?
... wg.Wait()
fmt.Println("Done")
}
However, it is rather pointless to call wg.Add over and over again when you already know how many times it will be called.
Waitgroups panic if the counter falls below zero. The counter starts at zero, each Done() is a -1 and each Add() depends on the paramet...
How to install a gem or update RubyGems if it fails with a permissions error
I'm trying to install a gem using gem install mygem or update RubyGems using gem update --system , and it fails with this error:
...
Best practices for catching and re-throwing .NET exceptions
... that bombs here
} catch (Exception ex)
{
throw;
}
throw ex; is basically like throwing an exception from that point, so the stack trace would only go to where you are issuing the throw ex; statement.
Mike is also correct, assuming the exception allows you to pass an exception (which is recom...
How to create a listbox in HTML without allowing multiple selection?
...m looking to create a simple listbox, but one of the requirements is to DISALLOW multiple selection. Most of the code for listboxes goes like this -
...
How to make layout with rounded corners..?
...
@nhouser9: actually it's more like "It works, but be warned that your foreground/content might draw in the corners". So depending on the use case it might 100% work. I'm glad the answer has not so many downvotes because it is useful, and I'...
Hide separator line on one UITableViewCell
...th.row != self.newCarArray.count-1){
UIImageView *line = [[UIImageView alloc] initWithFrame:CGRectMake(0, 44, 320, 2)];
line.backgroundColor = [UIColor redColor];
[cell addSubview:line];
}
for iOS 7 upper versions (including iOS 8)
if (indexPath.row == self.newCarArray.count-1) {
...
mysql error 1364 Field doesn't have a default values
...e makes MySQL more prone to data quality errors, so removing it is not a really good advice.
– Shadow
May 18 '17 at 8:59
...
How can I dynamically create a selector at runtime with Objective-C?
... theMethod:(id)methodArg];, you'd write...
void (^impBlock)(id,id) = ^(id _self, id methodArg) {
[_self doSomethingWith:methodArg];
};
and then you need to generate the IMP block dynamically, this time, passing, "self", the SEL, and any arguments...
void(*impFunct)(id, SEL, id) = (void*...
How do I assign an alias to a function name in C++?
...
Note: there is no way to make an alias to overloaded function such that all its overloaded versions work, so you should always specify which exact function overload you want.
With C++14 you can go even further with constexpr template variables. That allows you to alias templated functions:
templ...
What's the difference between Perl's backticks, system, and exec?
...It never returns true, because if the command is found it never returns at all.
There is also no point in returning STDOUT, STDERR or exit status of the command.
You can find documentation about it in perlfunc,
because it is a function.
system
executes a command and your Perl script is con...