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Best way to iterate through a Perl array
Which is the best implementation(in terms of speed and memory usage) for iterating through a Perl array? Is there any better way? ( @Array need not be retained).
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How to remove an element from a list by index
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Use del and specify the index of the element you want to delete:
>>> a = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
>>> del a[-1]
>>> a
[0, 1, 2, 3, 4, 5, 6, 7, 8]
Also supports slices:
>>> del a[2:4]
>...
Why does changing the sum order returns a different result?
...gnificant digits, where each addition is performed at "infinite" precision and then rounded to the nearest representable number. Here are two sums:
1/3 + 2/3 + 2/3 = (0.3333 + 0.6667) + 0.6667
= 1.000 + 0.6667 (no rounding needed!)
= 1.667 (where 1.6667 is rounded to...
What is the difference between procedural programming and functional programming? [closed]
I've read the Wikipedia articles for both procedural programming and functional programming , but I'm still slightly confused. Could someone boil it down to the core?
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Is there a MySQL option/feature to track history of changes to records?
...QL database. So when a field has been changed, the old vs new is available and the date this took place. Is there a feature or common technique to do this?
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How to shorten my conditional statements
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Put your values into an array, and check if your item is in the array:
if ([1, 2, 3, 4].includes(test.type)) {
// Do something
}
If a browser you support doesn't have the Array#includes method, you can use this polyfill.
Short explanation of the ...
How to create a self-signed certificate with OpenSSL
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You can do that in one command:
openssl req -x509 -newkey rsa:4096 -keyout key.pem -out cert.pem -days 365
You can also add -nodes (short for no DES) if you don't want to protect your private key with a passphrase. Otherwise it will prompt you for "...
What is the scope of variables in JavaScript?
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TLDR
JavaScript has lexical (also called static) scoping and closures. This means you can tell the scope of an identifier by looking at the source code.
The four scopes are:
Global - visible by everything
Function - visible within a function (and its sub-functions and blocks)
Bloc...
Regex Pattern to Match, Excluding when… / Except between
...ome useful ideas but I want something more complete that I can 100% understand and reuse; that's why I set a bounty. Also ideas that work everywhere are better for me than not standard syntax like \K
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HSL to RGB color conversion
...(which he attributes to a now defunct mjijackson.com, but is archived here and the original author has a gist - thanks to user2441511).
The code is re-posted below:
HSL to RGB:
/**
* Converts an HSL color value to RGB. Conversion formula
* adapted from http://en.wikipedia.org/wiki/HSL_color_sp...