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Specifying an Index (Non-Unique Key) Using JPA
...Table;
@Entity
@Table(name = "region",
indexes = {@Index(name = "my_index_name", columnList="iso_code", unique = true),
@Index(name = "my_index_name2", columnList="name", unique = false)})
public class Region{
@Column(name = "iso_code", nullable = false)
priva...
How can I be notified when an element is added to the page?
I want a function of my choosing to run when a DOM element is added to the page. This is in the context of a browser extension, so the webpage runs independently of me and I cannot modify its source. What are my options here?
...
Is there a function to make a copy of a PHP array to another?
... by reference. This means that:
$a = array();
$b = $a;
$b['foo'] = 42;
var_dump($a);
Will yield:
array(0) {
}
Whereas:
$a = new StdClass();
$b = $a;
$b->foo = 42;
var_dump($a);
Yields:
object(stdClass)#1 (1) {
["foo"]=>
int(42)
}
You could get confused by intricacies such as Ar...
C-like structures in Python
...uct(NamedTuple):
foo: str
bar: int
baz: list
qux: User
my_item = MyStruct('foo', 0, ['baz'], User('peter'))
print(my_item) # MyStruct(foo='foo', bar=0, baz=['baz'], qux=User(name='peter'))
share
...
Why can a class not be defined as protected?
Why can we not define a class as protected ?
12 Answers
12
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How do I inspect the view hierarchy in iOS?
...
I've got: error: cannot find interface declaration for '$__lldb_objc_class' any ideas? (lldb) po [[UIWindow keyWindow] recursiveDescription] error: cannot find interface declaration for '$__lldb_objc_class' error: cannot find interface declaration for '$__lldb_objc_class' error:...
Sell me on const correctness
...g object.
– Adrian
Mar 19 '18 at 21:32
|
show 1 more comment
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What are some resources for getting started in operating system development? [closed]
...Adam Davis
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...
Thou shalt not inherit from std::vector
Ok, this is really difficult to confess, but I do have a strong temptation at the moment to inherit from std::vector .
13...
ValueError: The truth value of an array with more than one element is ambiguous. Use a.any() or a.al
...rrays causes the two arrays to be evaluated in boolean context (by
calling __bool__ in Python3 or __nonzero__ in Python2).
Your original code
mask = ((r["dt"] >= startdate) & (r["dt"] <= enddate))
selected = r[mask]
looks correct. However, if you do want and, then instead of a and b u...