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For-each over an array in JavaScript
... from its prototype), and
That the key is all decimal digits (e.g., normal string form, not scientific notation), and
That the key's value when coerced to a number is <= 2^32 - 2 (which is 4,294,967,294). Where does that number come from? It's part of the definition of an array index in the speci...
Replace a value if null or undefined in JavaScript
... If anything falsey is a potentially valid input (0, false, empty string), I would do something like this instead: var j = (i === null) ? 10 : i; Which will only replace null, rather than anything that can be evaluated to false.
– DBS
Sep 26 '16 at 11:...
What characters can be used for up/down triangle (arrow without stem) for display in HTML?
...POINTING TRIANGLE
▼ - U+25BC BLACK DOWN-POINTING TRIANGLE
▴ - U+25B4 SMALL BLACK UP-POINTING TRIANGLE
▾ - U+25BE SMALL BLACK DOWN-POINTING TRIANGLE
For ▲ and ▼ use &#x25B2; and &#x25BC; respectively if you cannot include Unicode characters directly (use UTF-8!).
Note that the fo...
List comprehension on a nested list?
...t of lists, similar to what you started with except with floats instead of strings. If you want one flat list then you would use [float(y) for x in l for y in x].
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Does PostgreSQL support “accent insensitive” collations?
...the function in the right expression. There you can also supply unaccented strings like 'Joao' directly.
The faster function does not translate to much faster queries using the expression index. That operates on pre-computed values and is very fast already. But index maintenance and queries not usi...
How do I enter RGB values into Interface Builder?
...bers do not spec a color, you also need to know the colorspace. It's like string encodings. 65 is the ASCII encoding of A. The colorspace with which to encode/decode the components is in the little dropdown to the left of "RGB" sliders above. The "Generic RGB" colorspace corresponds to colors made...
How do I use Node.js Crypto to create a HMAC-SHA1 hash?
... // can't read from the stream until you call end()
hash = hmac.read().toString('hex'); // read out hmac digest
console.log("Method 1: ", hash);
// Method 2 - Using update and digest:
hmac = crypto.createHmac(algorithm, secret);
hmac.update(text);
hash = hmac.digest('hex');
console.log("Method...
java: Class.isInstance vs Class.isAssignableFrom
...e code to demonstrate:
public class NewMain
{
public static void main(String[] args)
{
NewMain nm = new NewMain();
nm.doit();
}
class A { }
class B extends A { }
public void doit()
{
A myA = new A();
B myB = new B();
A[] aArr = ...
Why sizeof int is wrong, while sizeof(int) is right?
... be ambiguous if C++ didnt specify that the new operator takes the longest string that could possibly be a type. So In C++ they could have made the same with sizeof, I guess. But in C++ you can say sizeof int() which then would have been ambiguous (type or value initialized int?).
...
WPF Data Binding and Validation Rules Best Practices
...an use INotifyErrorInfo which allows you to return objects instead of just strings.
– Peter
Dec 19 '13 at 8:44
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