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How do I iterate over an NSArray?
...
The generally-preferred code for 10.5+/iOS.
for (id object in array) {
// do something with object
}
This construct is used to enumerate objects in a collection which conforms to the NSFastEnumeration protocol. This approach ha...
Create a dictionary on a list with grouping
...vert it to a dictionary, as follows:
Dim qry = (From acs In ActualSales _
Group By acs.ProductID Into Group _
Select ProductID, Months = Group.ToDictionary(Function(c) c.Period) _
).ToDictionary(Function(c) c.ProductID)
The resulting query can be used as fo...
MongoDB drop every database
..."dropping db " + db.getName() );
db.dropDatabase();
}
save it to dropall.js and then execute:
mongo dropall.js
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Define variable to use with IN operator (T-SQL)
... myColumn in (SELECT id FROM myIdTable WHERE id > 10)
2) Using dynamically concatenated TSQL
DECLARE @sql varchar(max)
declare @list varchar(256)
select @list = '1,2,3'
SELECT @sql = 'SELECT * FROM myTable WHERE myColumn in (' + @list + ')'
exec sp_executeSQL @sql
3) A possible third ...
Detecting a mobile browser
...
@RichardLovejoy when building sites, the ipad is generally not considered a mobile.
– Michael Zaporozhets
Mar 28 '13 at 11:14
43
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querySelector, wildcard element match?
...to do a wildcard element name match using querySelector or querySelectorAll ? I see support for wildcards in attribute queries but not for the elements themselves.
...
List comprehension: Returning two (or more) items for each item
...bda x: x + 2
>>> g = lambda x: x ** 2
>>> list(chain.from_iterable((f(x), g(x)) for x in range(3)))
[2, 0, 3, 1, 4, 4]
Timings:
from timeit import timeit
f = lambda x: x + 2
g = lambda x: x ** 2
def fg(x):
yield f(x)
yield g(x)
print timeit(stmt='list(chain.from_itera...
How do you iterate through every file/directory recursively in standard C++?
...e to the standard.
An example, taken straight from the website:
bool find_file( const path & dir_path, // in this directory,
const std::string & file_name, // search for this name,
path & path_found ) // placing path here if found
{
...
What is the difference between public, protected, package-private and private in Java?
...e MyClass and I'm doing AnotherClass extends MyClass I will have access to all protected and public methods and properties from within AnotherClass. If I do MyClass myClass = new MyClass(); in AnotherClass somewhere - let's say the constructor - I will only have access to the public methods if it is...
How to check if an email address exists without sending an email?
...here are two methods you can sometimes use to determine if a recipient actually exists:
You can connect to the server, and issue a VRFY command. Very few servers support this command, but it is intended for exactly this. If the server responds with a 2.0.0 DSN, the user exists.
VRFY user
You can...