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javascript set a variable if undefined
...true // true
c ??= true // false
// Equivalent to
a = a ?? true
Object/Array Examples
let x = ["foo"]
let y = { foo: "fizz" }
x[0] ??= "bar" // "foo"
x[1] ??= "bar" // "bar"
y.foo ??= "buzz" // "fizz"
y.bar ??= "buzz" // "buzz"
x // Array [ "foo", "bar" ]
y // Object { foo: "fizz", bar:...
not None test in Python [duplicate]
...commended: If val can be either None or a more complex thing, like a numpy array, it's not entirely clear whether this intends to be an element-wise comparison (e.g: arr>0 will produce a list of indices at which elements of arr are positive), so if you expect val to be either an array or None, t...
How to compare 2 files fast using .NET?
... a similar comparison, but instead of one byte at a time, you would use an array of bytes sized to Int64, and then compare the resulting numbers.
Here's what I came up with:
const int BYTES_TO_READ = sizeof(Int64);
static bool FilesAreEqual(FileInfo first, FileInfo second)
{
i...
Checking if an instance's class implements an interface?
...he expensive __construct() is:
public function __construct() {
$tmp = array(
'foo' => 'bar',
'this' => 'that'
);
$in = in_array('those', $tmp);
}
These tests are based on this simple code.
...
Converting Symbols, Accent Letters to English Alphabet
... search bibliographic data that included diacritic characters. The lookup arrays (as it was in our case) took perhaps 1 man day to produce, to cover all diacritic marks for all Western European languages.
share
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...
Placement of the asterisk in pointer declarations
...replace them with
the corresponding english statements:
[X] or []: Array X size of... or Array undefined size of...
(type1, type2): function passing type1 and type2 returning...
*: pointer(s) to...
Keep doing this in a spiral/clockwise direction until all tokens have been covere...
How do I use the lines of a file as arguments of a command?
...ers, etc), it gets a bit more interesting.
To write to a file, given an array of arguments:
printf '%s\0' "${arguments[@]}" >file
...replace with "argument one", "argument two", etc. as appropriate.
To read from that file and use its contents (in bash, ksh93, or another recent shell with...
Why is it necessary to set the prototype constructor?
...) when building the new promise to return. It's also involved in subtyping arrays (via ArraySpeciesCreate).
Outside of the language itself, sometimes people would use it when trying to build generic "clone" functions or just generally when they wanted to refer to what they believed would be the obj...
What is the difference between SAX and DOM?
...sume that in his application, the instructor use no data structure such as arrays to store the student personal information and the points.
If the instructor decides to give A's to those who earned the class average or above, and give B's to the others, then he'd better to use a DOM parser in his a...
String concatenation in Ruby
...s of strings you often can gain performance by appending the strings to an array and then at the end put the string together atomically. Then << could be useful?
– PEZ
Dec 18 '08 at 13:12
...