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In Functional Programming, what is a functor?
...fmap even
is an overloaded function that can do many wonderful things:
Convert a list of integers to a list of Booleans
Convert a tree of integers to a tree of Booleans
Convert Nothing to Nothing and Just 7 to Just False
In Haskell, this property is expressed by giving the type of fmap:
fmap ...
How to change string into QString?
...
If compiled with STL compatibility, QString has a static method to convert a std::string to a QString:
std::string str = "abc";
QString qstr = QString::fromStdString(str);
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How to concatenate strings of a string field in a PostgreSQL 'group by' query?
...at the question asked for, even letting you specify the delimiter string:
SELECT company_id, string_agg(employee, ', ')
FROM mytable
GROUP BY company_id;
Postgres 9.0 also added the ability to specify an ORDER BY clause in any aggregate expression; otherwise, the order is undefined. So you can no...
Update statement with inner join on Oracle
...sn't valid in Oracle. You can do this:
UPDATE table1 SET table1.value = (SELECT table2.CODE
FROM table2
WHERE table1.value = table2.DESC)
WHERE table1.UPDATETYPE='blah'
AND EXISTS (SELECT table2.CODE
FROM table2
...
Is there a Python equivalent to Ruby's string interpolation?
...nd text found in the example in the documentation however. Why the use of convert to string here: %(language)s What does the 3 in '03d' signify? Why after the string is there % \? The assignment of variables (if they are in fact variables) after the print expression confuses me also. Sorry if t...
What is the best way to conditionally apply a class?
...ul with an li for each element and a property on the controller called selectedIndex . What would be the best way to add a class to the li with the index selectedIndex in AngularJS?
...
How to animate the change of image in an UIImageView?
...ill first cross dissolve a new image and then add a bouncy animation:
var selected: Bool {
willSet(selected) {
let expandTransform:CGAffineTransform = CGAffineTransformMakeScale(1.15, 1.15);
if (!self.selected && selected) {
UIView.transitionWithView(self.imageView,
...
PHP PDO returning single row
...
$dbh = new PDO(" --- connection string --- ");
$stmt = $dbh->prepare("SELECT name FROM mytable WHERE id=4 LIMIT 1");
$stmt->execute();
$row = $stmt->fetch();
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Mongoose, Select a specific field with find
I'm trying to select only a specific field with
8 Answers
8
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Unbound classpath container in Eclipse
... or 4. goto Properties -> Java Build Path -> Libraries Tab -> Select the erroneous system library -> Edit (On the right) -> Select alternate JRE -> Finish.
– Rajkiran
Jun 26 '14 at 12:11
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