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C++ where to initialize static const
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Anywhere in one compilation unit (usually a .cpp file) would do:
foo.h
class foo {
static const string s; // Can never be initialized here.
static const char* cs; // Same with C strings.
static const int i = 3; // Integral types can be initialized...
What is NSZombie?
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It's a memory debugging aid. Specifically, when you set NSZombieEnabled then whenever an object reaches retain count 0, rather than being deallocated it morphs itself into an NSZombie instance. Whenever such a zombie receives a message, it logs a warning rather ...
How is Generic Covariance & Contra-variance Implemented in C# 4.0?
...hat will become IEnumerable<out T>. That doesn't hurt type safety at all, but lets you return an IEnumerable<string> from a method declared to return IEnumerable<object> for instance.
Contravariance is harder to give concrete examples for using interfaces, but it's easy with a del...
MySQL Creating tables with Foreign Keys giving errno: 150
... CONSTRAINT's ON DELETE rule is SET NULL make sure the foreign key can actually be NULL! I spent 30 minutes reading this answer over and over, making sure my tables met the conditions but still getting Error 150. Then I noticed my FK was a NOT NULL field meaning the rule was impossible to apply.
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Byte[] to InputStream or OutputStream
...it to InputStream or OutputStream . But I don't know what happens internally when I do so. Can anyone briefly explain me what's happening when I do this conversion?
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jQuery - multiple $(document).ready …?
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All will get executed and On first Called first run basis!!
<div id="target"></div>
<script>
$(document).ready(function(){
jQuery('#target').append('target edit 1<br>');
});
$(document).rea...
How to export JavaScript array info to csv (on client side)?
...ure but I need to do this using JavaScript. I am using Dojo 1.8 and have all the attribute info in array, which looks like this:
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Formatting a number with exactly two decimals in JavaScript
...35"
You can alternatively use the toLocaleString method, which internally will use the Intl API:
const format = (num, decimals) => num.toLocaleString('en-US', {
minimumFractionDigits: 2,
maximumFractionDigits: 2,
});
console.log(format(2.005)); // "2.01"
console.log(format...
Adding a column to a data.frame
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@RomanLuštrik, This solution can be rewritten really nicely in a single line. Using your your.df data, you can simply do your.df$group = cumsum(your.df[, 1]==1) to get your new group column.
– A5C1D2H2I1M1N2O1R2T1
Apr 16 '12 at 17:47
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Open file via SSH and Sudo with Emacs
...: or su:hostname: with remote hosts.
The trap here is that sudo:: does actually appear to work -- however when you do that the HOST for the dynamic proxy entry will be the hostname you originated from rather than the host you connected to. This will not only look confusing (as the wrong host will be...