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List comprehension in Ruby
...e an Array#comprehend method like this:
class Array
def comprehend(&block)
return self if block.nil?
self.collect(&block).compact
end
end
some_array = [1, 2, 3, 4, 5, 6]
new_array = some_array.comprehend {|x| x * 3 if x % 2 == 0}
puts new_array
Prints:
6
12
18
I would prob...
Does ARC support dispatch queues?
...mpiler. This allows
* them to participate in ARC, in RR management by the Blocks runtime and in
* leaks checking by the static analyzer, and enables them to be added to Cocoa
* collections.
*
* NOTE: this requires explicit cancellation of dispatch sources and xpc
* connections whose hand...
Is it possible to capture a Ctrl+C signal and run a cleanup function, in a “defer” fashion?
...to get processor time to handle the signal, the main goroutine must call a blocking operation or call runtime.Gosched in an appropriate place (in your program's main loop, if it has one)
– misterbee
Aug 4 '13 at 15:53
...
Nginx — static file serving confusion with root & alias
...stuff like "received request for [...], matched by "location [...]" config block, searching directory [...]"
– Pistos
Jun 5 '18 at 17:18
2
...
How can I replace text with CSS?
...;
padding: 5px;
}
Now let's hide the original element, but add another block element afterwards:
button {
visibility: hidden;
}
button:after {
content:'goodbye';
visibility: visible;
display: block;
position: absolute;
background-color: red;
padding: 5px;
top: 2px;
}
Note:
...
Difference between a “coroutine” and a “thread”?
... have a routine doing some work and it performs an operation you know will block for some time (i.e. a network request), with a co-routine you can immediately switch to another routine without the overhead of including the system scheduler in this decision - yes you the programmer must specify when ...
What's the difference between a web site and a web application? [closed]
...ites are primarily informational. In this sense, http://cnn.com and http://php.net are websites, not web applications.
Web applications primarily allow the user to perform actions. Google Analytics, gmail, and jslint are web applications.
They are not entirely exclusive. A university website lik...
Number of rows affected by an UPDATE in PL/SQL
... cannot be directly accessed from an SQL command. By using a noname PL/SQL block, this can be achieved.
... If anyone has a solution to use it in a SELECT Command, I would be interested.
share
|
im...
Difference between wait() and sleep()
...aited on whereas a sleep cannot. Also a wait (and notify) must happen in a block synchronized on the monitor object whereas sleep does not:
Object mon = ...;
synchronized (mon) {
mon.wait();
}
At this point the currently executing thread waits and releases the monitor. Another thread may do
...
How to declare a type as nullable in TypeScript?
...y might be invalid. To make the code robust, you should probably use an if block to check for null first, like this: if (emp) { console.log(emp.id); } If you use such an if-block, the TypeScript compiler and the editor "see" that the object inside the block is not null and thus will not generate err...