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When should you use 'friend' in C++?
...d was curious about the friend declaration. I personally have never used it, however I am interested in exploring the language.
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Hash function that produces short hashes?
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You can use any commonly available hash algorithm (eg. SHA-1), which will give you a slightly longer result than what you need. Simply truncate the result to the desired length, which may be good enough.
For example, in Python:
>>> import hashlib
>>>...
(Built-in) way in JavaScript to check if a string is a valid number
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To check if a variable (including a string) is a number, check if it is not a number:
This works regardless of whether the variable content is a string or number.
isNaN(num) // returns true if the variable does NOT contain a valid number
Examples
isNaN(123) // false
isN...
Where can I find php.ini?
...php file and add the following code:
<?php phpinfo(); ?>
and open it in browser, it will show the file which is actually being read!
Updates by OP:
The previously accepted answer is likely to be faster and more convenient for you, but it is not always correct. See comments on that answer...
Simple way to convert datarow array to datatable
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Why not iterate through your DataRow array and add (using DataRow.ImportRow, if necessary, to get a copy of the DataRow), something like:
foreach (DataRow row in rowArray) {
dataTable.ImportRow(row);
}
Make sure your dataTable ...
When should we use intern method of String on String literals
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Java automatically interns String literals. This means that in many cases, the == operator appears to work for Strings in the same way that it does for ints or other primitive values.
Since interning is automatic for String literals, the intern() method is to...
Is there a Python equivalent of the C# null-coalescing operator?
In C# there's a null-coalescing operator (written as ?? ) that allows for easy (short) null checking during assignment:
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Where is the .NET Framework 4.5 directory?
...what about this page from MSDN. msdn.microsoft.com/en-us/library/bb397428. It mentions a 4.5.0.0 directory?
– Nick Randell
Aug 22 '12 at 9:56
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Best way to use Google's hosted jQuery, but fall back to my hosted library on Google fail
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You can achieve it like this:
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.2.6/jquery.min.js"></script>
<script>
window.jQuery || document.write('<script src="/path/to/your/jquery"><\/script...
jQuery Validate - require at least one field in a group to be filled
...up of fields. I think I've got a pretty good solution, and wanted to share it. Please suggest any improvements you can think of.
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