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Switch statement: must default be the last case?
...se 0:
// here goes the timeout case
break;
case -1:
// some error occurred, you have to check errno
}
The point is that the above code is more readable and efficient than cascaded if. You could put default at the end, but it is pointless as it will focus your attention on error case...
How can a windows service programmatically restart itself?
...aviour but a returncode of 1 is meant to tell the system that there was an error. Isn't this bad practice if there was in fact no error and you just wanted to restart your service?
– mgttlinger
May 29 '13 at 13:47
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INSERT with SELECT
...e, location, '$this->gid' FROM courses WHERE cid = $cid -- I get the error: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'name, location, gid SELECT name, location, '22' FROM courses WHERE cid = 23' a...
When should I use double instead of decimal?
...ously decimals) can't be truly represented in floating point form
rounding errors occur, just as if you were doing the calculation by hand. It depends greatly on the context (how many operations you're performing) whether these errors are significant enough to warrant much thought however.
In all...
django admin - add custom form fields that are not part of the model
...
@sthzg, Because it's not correct. It gives me the error: YourModelAdmin.list_display[0], 'extra_field' is not a callable or an attribute of 'YourModelAdmin' or found in the model 'YourModel'.
– Cerin
Jun 13 '16 at 15:39
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Is 'float a = 3.0;' a correct statement?
...
It is not an error to declare float a = 3.0 : if you do, the compiler will convert the double literal 3.0 to a float for you.
However, you should use the float literals notation in specific scenarios.
For performance reasons:
Specif...
How to list all installed packages and their versions in Python?
... It doesn't support python 3 (just installed from pip and got runtime errors)
– Ohad Cohen
Apr 28 '18 at 13:57
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How do I verify/check/test/validate my SSH passphrase?
... ssh-add requires admin rights on the machine, I think. I am getting an error: "Could not open a connection to your authentication agent."
– IgorGanapolsky
Feb 12 '14 at 21:15
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What is the function of the DBMDL File in VS database project
...tion results in a "contains a reference to a project which does not exist" error from database project to server project that doesn't show up again on subsequent loads.
– Mayo
Dec 31 '10 at 16:10
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Better naming in Tuple classes than “Item1”, “Item2”
...er, don't use it for this simple case as what would have been compile-time errors become run-time errors.
class Program
{
static void Main(string[] args)
{
dynamic employee, manager;
employee = new ExpandoObject();
employee.Name = "John Smith";
employee.Age ...