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What’s the difference between “Array()” and “[]” while declaring a JavaScript array?
...hese are the same
b = new Array(), // a and b are arrays with length 0
c = ['foo', 'bar'], // these are the same
d = new Array('foo', 'bar'), // c and d are arrays with 2 strings
// these are different:
e = [3] // e.length == 1, e[0] == 3
f = new Ar...
JavaScript checking for null vs. undefined and difference between == and ===
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+50
How do I check a variable if it's null or undefined...
Is the variable null:
if (a === null)
// or
if (a == null) // but see not...
What does = +_ mean in JavaScript
...values true, false, and null.
Integers in both decimal and hexadecimal ("0x"-prefixed) formats are
supported. Negative numbers are supported (though not for hex). If it
cannot parse a particular value, it will evaluate to NaN.
It is also noted that
unary plus is the fastest and preferred...
Insert a string at a specific index
....splice = function(start, delCount, newSubStr) {
return this.slice(0, start) + newSubStr + this.slice(start + Math.abs(delCount));
};
}
Example
String.prototype.splice = function(idx, rem, str) {
return this.slice(0, idx) + str + this.slice(idx + Math.abs(rem));
};
var re...
git pull from master into the development branch
... and thus recoverable from, the reflog. This also enables a new git 1.9/2.0 feature for finding upstream rebases.)
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How do API Keys and Secret Keys work? Would it be secure if I have to pass my API and secret keys to
...
90
Basically elaborating on what's outlined here.
Here's how it works: let's say we have a functio...
How to get a specific version of a file in Mercurial?
...
answered Jan 21 '10 at 14:32
djcdjc
10.6k44 gold badges3535 silver badges4747 bronze badges
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When and why would you seal a class?
...
10
The reason #1 sounds vague but, assuming we don't write "security features" most of the time, does that mean reason #1 hardly applies? Reaso...
What makes a SQL statement sargable?
...a function in the where clause:
SELECT ... FROM ...
WHERE Year(myDate) = 2008
The SQL optimizer can't use an index on myDate, even if one exists. It will literally have to evaluate this function for every row of the table. Much better to use:
WHERE myDate >= '01-01-2008' AND myDate < '01-0...
Final arguments in interface methods - what's the point?
...
106
It doesn't seem like there's any point to it. According to the Java Language Specification 4.12...