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What's the difference between isset() and array_key_exists()? [duplicate]
...n an array, whereas isset will only return true if the key/variable exists and is not null.
$a = array('key1' => 'フーバー', 'key2' => null);
isset($a['key1']); // true
array_key_exists('key1', $a); // true
isset($a['key2']); // false
array_key_exists('key2', $a...
HTTP response code for POST when resource already exists
...s where it is expected that the user might be able to resolve the conflict and resubmit the request. The response body SHOULD include enough information for the user to recognize the source of the conflict. Ideally, the response entity would include enough information for the user or user agent to f...
Query for documents where array size is greater than 1
...
2.Create extra field NamesArrayLength, update it with names array length and then use in queries:
db.accommodations.find({"NamesArrayLength": {$gt: 1} });
It will be better solution, and will work much faster (you can create index on it).
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How do you automate Javascript minification for your Java web applications?
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minify-maven and maven yui compressor didn't play nice with ES6 features for me as of the time of this comment
– DPM
Dec 5 '17 at 16:17
...
npm global path prefix
...Homebrew).
So:
npm config set prefix /usr/local if it's something else, and
Don't use sudo with npm! According to the jslint docs, you should just be able to npm install it.
If you installed npm as sudo (sudo brew install), try reinstalling it with plain ol' brew install. Homebrew is supposed t...
Replace multiple whitespaces with single whitespace in JavaScript string
...whitespaces with the same kind of whitespace? (e.g. 2+ spaces with a space and 3 newlines with a newline, etc.) if there are both newlines and spaces it would have to be replaced by a newline whereas if there are both spaces and tabs it would have to be replaced by a space
– To...
lenses, fclabels, data-accessor - which library for structure access and mutation is better
There are at least three popular libraries for accessing and manipulating fields of records. The ones I know of are: data-accessor, fclabels and lenses.
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How to format a number as percentage in R?
...scales package, as documented in krlmlr's answer. Use that instead of my hand-rolled solution.
Try something like
percent <- function(x, digits = 2, format = "f", ...) {
paste0(formatC(100 * x, format = format, digits = digits, ...), "%")
}
With usage, e.g.,
x <- c(-1, 0, 0.1, 0.5555...
What is the difference between a.getClass() and A.class in Java?
...oth in different circumstances (just like there are with Class.forName() and ClassLoader.loadClass() .
7 Answers
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In c++ what does a tilde “~” before a function name signify?
...scription from ibm.com:
Destructors are usually used to deallocate memory and do other cleanup for a class object and its class members when the object is destroyed. A destructor is called for a class object when that object passes out of scope or is explicitly deleted.
See https://www.ibm.com/sup...