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Select random row from a sqlite table

... the day seeded with unix epoc for today at noon so it shows the same book all day even if the query is run multiple times. Yes I know caching is more efficient for this use case just an example. – danielson317 Apr 22 at 17:18 ...
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Casting vs using the 'as' keyword in the CLR

...d within the if body.) That's slightly annoying in some cases, so if you really care about introducing the smallest number of variables possible in every scope, you might still want to use is followed by a cast. I don't think any of the answers so far (at the time of starting this answer!) have r...
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What is a NullPointerException, and how do I fix it?

... When you declare a reference variable (i.e. an object) you are really creating a pointer to an object. Consider the following code where you declare a variable of primitive type int: int x; x = 10; In this example, the variable x is an int and Java will initialize it to 0 for you. When yo...
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Is there a function to make a copy of a PHP array to another?

...ewLarsson raises a point in the comments below. PHP has a special feature called "references". They are somewhat similar to pointers in languages like C/C++, but not quite the same. If your array contains references, then while the array itself is passed by copy, the references will still resolve to...
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Add Variables to Tuple

... I think its important to note that tuples are immutable - they cannot actually be modified. What this solution does is create a new tuple based on two existing tuples. – That1Guy Jan 16 '19 at 20:58 ...
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Understanding the map function

...d, function must take that many arguments and is applied to the items from all iterables in parallel. 6 Answers ...
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How to pass variable from jade template file to a script file?

...ex's answer correctly encodes the string (newlines in the login name could allow code execution). – Paul Grove Nov 8 '16 at 18:13 ...
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PHP global in functions

...ngletons, registries, constants). You do not want to use them. A function call should not have to rely on anything outside, e.g. function fn() { global $foo; // never ever use that $a = SOME_CONSTANT // do not use that $b = Foo::SOME_CONSTANT; // do not use that unl...
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What it the significance of the Javascript constructor property?

...the constructor property is used in a few places. However, I think the overall gist still applies. Thanks to T. J. Crowder for pointing that out in the comments, and please read his answer for a fuller picture of the current situation. Original answer The constructor property makes absolutely no pra...
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Ignore .pyc files in git repository

...t to to do it beforehand, if you just add the line to the .gitignore file, all previously committed .pyc files will still be tracked, so you'll need to remove them from the repository. If you are on a Linux system (or "parents&sons" like a MacOSX), you can quickly do it with just this one line ...