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Using a strategy pattern and a command pattern
...s encapsulate an algorithm and decouple implementation details from their calling classes. The only difference I can discern is that the Strategy pattern takes in parameters for execution, while the Command pattern doesn't.
...
Command to get nth line of STDOUT
...ssage:
ls -l | sed -n -e '2{p;q}'
I've seen that often enough that I usually use the first (which is easier to type, anyway), though ls is not a command that complains when it gets SIGPIPE.
For a range of lines:
ls -l | sed -n 2,4p
For several ranges of lines:
ls -l | sed -n -e 2,4p -e 20,30...
CORS: Cannot use wildcard in Access-Control-Allow-Origin when credentials flag is true
...
This is a part of security, you cannot do that. If you want to allow credentials then your Access-Control-Allow-Origin must not use *. You will have to specify the exact protocol + domain + port. For reference see these questions :
Access-Control-Allow-Origin wildcard subdomains, ports...
connecting to MySQL from the command line
... authentication based on the user you logged in as, or not authenticate at all, but neither is a good idea, Specifying the password on the command line is even a slight security risk because it ends up in your command history and process tables. If you leave out the password it will ask you for it...
Read file line by line using ifstream in C++
... read data from a file:
std::ifstream input( "filename.ext" );
If you really need to read line by line, then do this:
for( std::string line; getline( input, line ); )
{
...for each line in input...
}
But you probably just need to extract coordinate pairs:
int x, y;
input >> x >&g...
phantomjs not waiting for “full” page load
...der, as per the regular rasterize.js example, but with a longer timeout to allow the JavaScript to finish loading additional resources:
page.open(address, function (status) {
if (status !== 'success') {
console.log('Unable to load the address!');
phantom.exit();
} else {
...
What is InnoDB and MyISAM in MySQL?
...MyISAM
InnoDB is a storage engine for MySQL,
included as standard in all current
binaries distributed by MySQL AB. Its
main enhancement over other storage
engines available for use with MySQL
is ACID-compliant transaction support
MyISAM is the default storage engine
for the MySQ...
COALESCE Function in TSQL
...not sure why you think the documentation is vague.
It simply goes through all the parameters one by one, and returns the first that is NOT NULL.
COALESCE(NULL, NULL, NULL, 1, 2, 3)
=> 1
COALESCE(1, 2, 3, 4, 5, NULL)
=> 1
COALESCE(NULL, NULL, NULL, 3, 2, NULL)
=> 3
COALESCE(6, 5, 4, ...
simulate background-size:cover on or
... that it doesn't handle scaling correctly. If the surrounding element is smaller than the video file, it isn't scaled down. Even if you give the video tag a tiny initial size, like 16px by 9px, auto ends up forcing it to a minimum of its native file-size. With the current top-voted solution on this ...
Why is “final” not allowed in Java 8 interface methods?
...es of Java 8 are the new default methods on interfaces. There are essentially two reasons (there may be others) why they have been introduced:
...
