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PHP Constants Containing Arrays?
...FAULT_ROLES = ['guy', 'development team'];
If you have PHP 7, you can finally use define(), just as you had first tried:
<?php
define('DEFAULT_ROLES', array('guy', 'development team'));
share
|
...
How to find if a given key exists in a C++ std::map
...a particular key exists."
The documentation for map::count says: "Because all elements in a map container are unique, the function can only return 1 (if the element is found) or zero (otherwise)."
To retrieve a value from the map via a key that you know to exist, use map::at:
value = m.at(key)
...
Get loop counter/index using for…of syntax in JavaScript
...bj] of enumerate(myArray)) {
console.log(i, obj);
}
demo
If you actually did mean for…in – enumerating properties – you would need an additional counter. Object.keys(obj).forEach could work, but it only includes own properties; for…in includes enumerable properties anywhere on the pro...
How to iterate over a JavaScript object?
...one you made yourself with {}).
This MDN documentation explains more generally how to deal with objects and their properties.
If you want to do it "in chunks", the best is to extract the keys in an array. As the order isn't guaranteed, this is the proper way. In modern browsers, you can use
let k...
How to get next/previous record in MySQL?
...IT 1;
edit: Since this answer has been getting a few upvotes lately, I really want to stress the comment I made earlier about understanding that a primary key colum is not meant as a column to sort by, because MySQL does not guarantee that higher, auto incremented, values are necessarily added at ...
How do I get the first n characters of a string without checking the size or going out of bounds?
...ngth(), n));
Opinion: while this solution is "neat", I think it is actually less readable than a solution that uses if / else in the obvious way. If the reader hasn't seen this trick, he/she has to think harder to understand the code. IMO, the code's meaning is more obvious in the if / else ve...
Difference between wait and sleep
... process ID or a job specification; if a
job spec is given, all processes in that job's pipeline are
waited for. If n is not given, all currently active child pro-
cesses are waited for, and the return status is zero. If n
specifies a non-existent proc...
Can we have functions inside functions in C++?
...rm of a lambda:
int main() {
// This declares a lambda, which can be called just like a function
auto print_message = [](std::string message)
{
std::cout << message << "\n";
};
// Prints "Hello!" 10 times
for(int i = 0; i < 10; i++) {
print...
How to extend an existing JavaScript array with another array, without creating a new array
...ethod can take multiple arguments. You can use the spread operator to pass all the elements of the second array as arguments to .push:
>>> a.push(...b)
If your browser does not support ECMAScript 6, you can use .apply instead:
>>> a.push.apply(a, b)
Or perhaps, if you think i...
Error: The processing instruction target matching “[xX][mM][lL]” is not allowed
...ng error
The processing instruction target matching "[xX][mM][lL]" is not allowed.
when an XML declaration is encountered anywhere other than at the top of an XML file.
This is a valid diagnostic message; other XML parsers should issue a similar error message in this situation.
To correct the p...