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Convert base class to derived class [duplicate]
Is it possible in C# to explicitly convert a base class object to one of it's derived classes? Currently thinking I have to create a constructor for my derived classes that accept a base class object as a parameter and copy over the property values. I don't really like this idea, so I'd like to avoi...
How do you set, clear, and toggle a single bit?
How do you set, clear, and toggle a bit?
30 Answers
30
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Mysql: Select rows from a table that are not in another
How to select all rows in one table that do not appear on another?
8 Answers
8
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Strange, unexpected behavior (disappearing/changing values) when using Hash default value, e.g. Hash
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First, note that this behavior applies to any default value that is subsequently mutated (e.g. hashes and strings), not just arrays.
TL;DR: Use Hash.new { |h, k| h[k] = [] } if you want the most idiomatic solution and don’t care why.
What do...
&& (AND) and || (OR) in IF statements
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No, it will not be evaluated. And this is very useful. For example, if you need to test whether a String is not null or empty, you can write:
if (str != null && !str.isEmpty()) {
doSomethingWith(str.charAt(0));
}
or, the other w...
How to count duplicate value in an array in javascript
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function count() {
array_elements = ["a", "b", "c", "d", "e", "a", "b", "c", "f", "g", "h", "h", "h", "e", "a"];
array_elements.sort();
var current = null;
var cnt = 0;
for (var i = 0; i < array_elements.length; i++) {
if (array_ele...
Obfuscated C Code Contest 2006. Please explain sykes2.c
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Let's de-obfuscate it.
Indenting:
main(_) {
_^448 && main(-~_);
putchar(--_%64
? 32 | -~7[__TIME__-_/8%8][">'txiZ^(~z?"-48] >> ";;;====~$::199"[_*2&8|_/64]/(_&2?1:8)%8&1
: 10);
}
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Natural Sort Order in C#
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The easiest thing to do is just P/Invoke the built-in function in Windows, and use it as the comparison function in your IComparer:
[DllImport("shlwapi.dll", CharSet = CharSet.Unicode)]
private static extern int StrCmpLogicalW(string psz1, string psz2);
Michael Kapla...
Replacements for switch statement in Python?
I want to write a function in Python that returns different fixed values based on the value of an input index.
44 Answers...
Python dictionary from an object's fields
Do you know if there is a built-in function to build a dictionary from an arbitrary object? I'd like to do something like this:
...