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How to check for null in Twig?
... other value that evaluates to false (such as zero, empty string and empty array). Besides, it will cause an error if var is not defined. A safer way would be:
{% if var is not defined or var is null %}
which can be shortened to:
{% if var|default is null %}
If you don't provide an argument to...
PHP Regex to check date is in YYYY-MM-DD format
...teTime::createFromFormat("Y-m-d", $date);
return $dt !== false && !array_sum($dt::getLastErrors());
This validates the input too: $dt !== false ensures that the date can be parsed with the specified format and the array_sum trick is a terse way of ensuring that PHP did not do "month shifti...
What do the following phrases mean in C++: zero-, default- and value-initialization?
...e object’s first named data member is zero-initialized;
— if T is an array type, each element is zero-initialized;
— if T is a reference type, no initialization is performed.
To default-initialize an object of type T means:
— if T is a non-POD class type (clause 9), the default ...
How do I pass command-line arguments to a WinForms application?
... i, args[i]);
}
}
The arguments will then be stored in the args string array:
$ AppB.exe firstArg secondArg thirdArg
args[0] == firstArg
args[1] == secondArg
args[2] == thirdArg
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improv...
C# Interfaces. Implicit implementation versus Explicit implementation
...mean: IList.CopyTo would be implicitly implemented as:
public void CopyTo(Array array, int index)
{
throw new NotImplementedException();
}
and explicitly as:
void ICollection.CopyTo(Array array, int index)
{
throw new NotImplementedException();
}
The difference is that implicit impleme...
Convert List to List
...urn BaseList.Contains((TFrom)(object)item); }
public void CopyTo(TTo[] array, int arrayIndex) { BaseList.CopyTo((TFrom[])(object)array, arrayIndex); }
public bool Remove(TTo item) { return BaseList.Remove((TFrom)(object)item); }
// IList
public TTo this[int index]
{
get ...
MVC (Laravel) where to add logic
...'congregations';
public function getValidator()
{
$data = array(
'name' => $this->name,
'address' => $this->address,
'pm_day_of_week' => $this->pm_day_of_week,
'pm_datetime' => $this->pm_datetime,
);
...
For every character in string
...(str[i]);
}
Looping through the characters of a null-terminated character array:
char* str = ???;
for(char* it = str; *it; ++it) {
do_things_with(*it);
}
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...
Why is sizeof considered an operator?
... I believe things are more complex nowadays due to variable-length arrays (VLA). IIRC, the standard would even allow sizeof to have side effects if there is a VLA in the expression.
– Aaron McDaid
Jan 27 '15 at 10:53
...
Why can't (or doesn't) the compiler optimize a predictable addition loop into a multiplication?
...swer by Mysticial to the question: why is it faster to process a sorted array than an unsorted array ?
7 Answers
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