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“Too many values to unpack” Exception
...project in Django and I've just started trying to extend the User model in order to make user profiles.
5 Answers
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What is the current directory in a batch file?
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how to provide a swap function for my class?
...that the standard library uses an unqualified call to the swap function in order to call user-defined swap for a user class if such user-defined swap is provided.
Swappable (cppreference.com):
Many standard library functions (for example, many algorithms) expect their arguments to satisfy Swapp...
Is there an equivalent of CSS max-width that works in HTML emails?
... of centered, just leave out the first empty cell.
Example:
<table border="0" cellspacing="0" width="100%">
<tr>
<td></td>
<td width="350">The width of this cell should be a maximum of
350 pixels, but shrink to widths less than...
Using mixins vs components for code reuse in Facebook React
...ycle methods (componentDidMount etc). This problem is solved by the Higher-Order Components that Dan Abramov talk in his link (or by using ES6 class inheritance).
Mixins are also often used in frameworks, to make framework API available to all the components, by using the "hidden" context feature o...
How to get the insert ID in JDBC?
...ults || iUpdCount!=-1)
{
//NOTE: in order for output parameters to be available,
//all resultsets must be processed
rs = callstmt.getResultSet();
//if rs is not null, we know we can get the re...
The JPA hashCode() / equals() dilemma
... // this.getClass() == other.getClass()
// for the same reason. In order to support laziness PP might need to wrap
// my entity object in some kind of proxy, i.e. subclassing it.
@Override
public boolean equals(final Object obj) {
if (this == obj)
return true;...
Determine if running on a rooted device
... environment variable and checks if a "su" file exists in one of them.
In order to truly check for root access the "su" command must actually be run. If an app like SuperUser is installed, then at this point it may ask for root access, or if its already been granted/denied a toast may be shown indi...
Are parallel calls to send/recv on the same socket valid?
...ifferent threads, the OS will handle the synchronization.
However, if the order of sending/receiving is semantically significant, you yourself (respectively your code) have to ensure proper sequencing between the operations in the different threads - as is always the case with threads.
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What is the difference between packaged_task and async
...when they're done, and std::packaged_task if you want to wrap up things in order to move them to other threads or call them later. Or, to quote Christian:
In the end a std::packaged_task is just a lower level feature for implementing std::async (which is why it can do more than std::async if use...