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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-...
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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...
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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] =...
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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_...
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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 ...
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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, ...
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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...
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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 ...
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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(). ...
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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...