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How is Math.Pow() implemented in .NET Framework?
I was looking for an efficient approach for calculating a b (say a = 2 and b = 50 ). To start things up, I decided to take a look at the implementation of Math.Pow() function. But in .NET Reflector , all I found was this:
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How to make an immutable object in Python?
Although I have never needed this, it just struck me that making an immutable object in Python could be slightly tricky. You can't just override __setattr__ , because then you can't even set attributes in the __init__ . Subclassing a tuple is a trick that works:
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Why isn't vector a STL container?
Item 18 of Scott Meyers's book Effective STL: 50 Specific Ways to Improve Your Use of the Standard Template Library says to avoid vector <bool> as it's not an STL container and it doesn't really hold bool s.
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Where does 'Hello world' come from?
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Brian Kernighan actually wrote the first "hello, world" program as part of the documentation for the BCPL programming language developed by Martin Richards. BCPL was used while C was being developed at Bell Labs a few years b...
What is a Context Free Grammar?
... then the Wikipedia entry on formal grammar, I am left utterly and totally befuddled. Would someone be so kind as to explain what these things are?
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What does the restrict keyword mean in C++?
...t while restrict is not part of the C++ standard yet, that it is supported by many compilers and he recommends it's usage when available:
restrict keyword
! New to 1999 ANSI/ISO C standard
! Not in C++ standard yet, but supported by many C++ compilers
! A hint only, so ...
Explicit vs implicit SQL joins
...Performance wise, they are exactly the same (at least in SQL Server).
PS: Be aware that the IMPLICIT OUTER JOIN syntax is deprecated since SQL Server 2005. (The IMPLICIT INNER JOIN syntax as used in the question is still supported)
Deprecation of "Old Style" JOIN Syntax: Only A Partial Thing
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How to initialize HashSet values by construction?
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There is a shorthand that I use that is not very time efficient, but fits on a single line:
Set<String> h = new HashSet<>(Arrays.asList("a", "b"));
Again, this is not time efficient since you are constructing an array, converting to a list and using that list to create a set...
How to split a string, but also keep the delimiters?
I have a multiline string which is delimited by a set of different delimiters:
23 Answers
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Merge 2 arrays of objects
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If you want to merge 2 arrays of objects in JavaScript. You can use this one line trick
Array.prototype.push.apply(arr1,arr2);
For Example
var arr1 = [{name: "lang", value: "English"},{name: "age", value: "18"}];
var arr2 = [{name : "childs", value: '5'}...