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Fastest way to determine if an integer is between two integers (inclusive) with known sets of values
... operator.
if ((unsigned)(number-lower) <= (upper-lower))
in_range(number);
With a typical, modern computer (i.e., anything using twos complement), the conversion to unsigned is really a nop -- just a change in how the same bits are viewed.
Note that in a typical case, you can pre-...
Object comparison in JavaScript [duplicate]
...
Unfortunately there is no perfect way, unless you use _proto_ recursively and access all non-enumerable properties, but this works in Firefox only.
So the best I can do is to guess usage scenarios.
1) Fast and limited.
Works when you have simple JSON-style objects without m...
What is :: (double colon) in Python when subscripting sequences?
...n custom classes to make it do whatever you want
class C(object):
def __getitem__(self, k):
return k
# Single argument is passed directly.
assert C()[0] == 0
# Multiple indices generate a tuple.
assert C()[0, 1] == (0, 1)
# Slice notation generates a slice object.
assert C()[1:2:3] =...
Javascript - sort array based on another array
.... :)
Case 2: Original Question (Lodash.js or Underscore.js)
var groups = _.groupBy(itemArray, 1);
var result = _.map(sortArray, function (i) { return groups[i].shift(); });
Case 3: Sort Array1 as if it were Array2
I'm guessing that most people came here looking for an equivalent to PHP's array_...
Convert JavaScript string in dot notation into an object reference
... given somewhere (e.g. developer.mozilla.org/en/JavaScript/Reference/Global_Objects/… ).
– ninjagecko
Jun 18 '11 at 6:12
...
Is there a ceiling equivalent of // operator in Python?
...sy) floating-point conversion.
Here's a demonstration:
>>> from __future__ import division # a/b is float division
>>> from math import ceil
>>> b = 3
>>> for a in range(-7, 8):
... print(["%d/%d" % (a, b), int(ceil(a / b)), -(-a // b)])
...
['-7/3', -2, ...
Is it better in C++ to pass by value or pass by constant reference?
...r iterators and for function objects (lambdas, classes deriving from std::*_function).
This was especially true before the existence of move semantics. The reason is simple: if you passed by value, a copy of the object had to be made and, except for very small objects, this is always more expensive...
What are valid values for the id attribute in HTML?
...wed by any number of letters, digits ([0-9]), hyphens ("-"), underscores ("_"), colons (":"), and periods (".").
HTML 5 is even more permissive, saying only that an id must contain at least one character and may not contain any space characters.
The id attribute is case sensitive in XHTML.
As a ...
When and why will a compiler initialise memory to 0xCD, 0xDD, etc. on malloc/free/new/delete?
...oc().
0xBAADF00D Bad Food Memory allocated by LocalAlloc() with LMEM_FIXED,but
not yet written to.
0xFEEEFEEE OS fill heap memory, which was marked for usage,
but wasn't allocated by HeapAlloc() or LocalAlloc().
...
powershell 2.0 try catch how to access the exception
....downloadString('http://foo')
}
catch [Net.WebException] {
Write-Host $_.Exception.ToString()
}
The exception is in the $_ variable. You might explore $_ like this:
try {
$w = New-Object net.WebClient
$d = $w.downloadString('http://foo')
}
catch [Net.WebException] {
$_ | fl * -For...