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How to correctly implement custom iterators and const_iterators?
...e, std::iterator with random_access_iterator_tag.These base classes define all type definitions required by STL and do other work.
To avoid code duplication iterator class should be a template class and be parametrized by "value type", "pointer type", "reference type" or all of them (depends on impl...
PHP abstract properties
...get_class($this) . ' must have a $tablename');
}
}
To enforce this for all derived classes of Foo_Abstract you would have to make Foo_Abstract's constructor final, preventing overriding.
You could declare an abstract getter instead:
abstract class Foo_Abstract {
abstract public function get_...
What is the difference between map and flatMap and a good use case for each?
...ark-shell session:
First, some data - two lines of text:
val rdd = sc.parallelize(Seq("Roses are red", "Violets are blue")) // lines
rdd.collect
res0: Array[String] = Array("Roses are red", "Violets are blue")
Now, map transforms an RDD of length N into another RDD of length N.
For examp...
How to make ng-repeat filter out duplicate results
...sion of ui utils, you can just include ui.unique on its own. use bower install just for the module.
– Learning stats by example
Feb 11 '15 at 19:59
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e.printStackTrace equivalent in python
...
import traceback
traceback.print_exc()
When doing this inside an except ...: block it will automatically use the current exception. See http://docs.python.org/library/traceback.html for more information.
...
SQL Server: SELECT only the rows with MAX(DATE)
... HAVING t1.DateEntered = MAX(t2.DateEntered))
This is the fastest of all the queries supplied above. The query cost came in at 0.0070668.
The preferred answer above, by Mikael Eriksson, has a query cost of 0.0146625
You may not care about the performance for such a small sample, but in large...
Different font size of strings in the same TextView
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is there a way to move the characters which are small to the center in the vertical direction? Basically all the characters should be vertically centered regardless of the size.
– 500865
Sep 23 '16 at 22:16
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What is a stored procedure?
... a couple of ways. Most major DBMs support stored procedures; however, not all do. You will need to verify with your particular DBMS help documentation for specifics. As I am most familiar with SQL Server I will use that as my samples.
To create a stored procedure the syntax is fairly simple:
CRE...
“Code too large” compilation error in Java
...size for code in Java? I wrote a function with more than 10,000 lines. Actually, each line assigns a value to an array variable.
...
django: BooleanField, how to set the default value to true?
...fields/#django.forms.Field.initial ) like
class MyForm(forms.Form):
my_field = forms.BooleanField(initial=True)
If you're using a ModelForm, you can set a default value on the model field ( https://docs.djangoproject.com/en/2.2/ref/models/fields/#default ), which will apply to the resulting M...