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Are Exceptions in C++ really slow
I was watching Systematic Error Handling in C++—Andrei Alexandrescu he claims that Exceptions in C++ are very very slow.
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ERROR: Error 1005: Can't create table (errno: 121)
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I searched quickly for you, and it brought me here. I quote:
You will get this message if you're trying to add a constraint with a
name that's already used somewhere else
To check constraints use the following SQL query:
SELECT
constraint_n...
Getting a list item by index
...ess a list, which is an object, like an array
– PrashanD
Apr 26 '17 at 7:10
Does it return a copy of the object in the...
TypeScript sorting an array
... a property, bear in mind the above information about being able to short-hand number types. The below example works irrespective of the type.
var objectArray: { age: number; }[] = [{ age: 10}, { age: 1 }, {age: 5}];
var sortedArray: { age: number; }[] = objectArray.sort((n1,n2) => {
if (n1...
Placeholder Mixin SCSS/CSS
...t
As of Sass 3.4, this mixin can be written like so to work both nested and unnested:
@mixin optional-at-root($sel) {
@at-root #{if(not &, $sel, selector-append(&, $sel))} {
@content;
}
}
@mixin placeholder {
@include optional-at-root('::-webkit-input-placeholder') {
@cont...
Spring Test & Security: How to mock authentication?
...ntrollers are properly secured. Just in case someone changes things around and accidentally removes security settings.
7 A...
What should I do if the current ASP.NET session is null?
... the HttpApplication.AcquireRequestState event.
Your code runs in an IHttpHandler, that does not specify either the IRequiresSessionState or IReadOnlySessionState interface.
If you only have code in pages, you won't run into this. Most of my ASP .NET code uses Session without checking for null repe...
Show data on mouseover of circle
...ement to each circle, as the browser will take care of showing the tooltip and you don't need the mousehandler. The code would be something like
vis.selectAll("circle")
.data(datafiltered).enter().append("svg:circle")
...
.append("svg:title")
.text(function(d) { return d.x; });
If you...
Check if a div exists with jquery [duplicate]
... though I can't think of how this would come up, that you need to run thousands of select queries over and over). It's just much more verbose, over the course of a lot of javascript that really adds up to more space and less readability.
– Jamie Treworgy
Aug 1 ...
Creating .pem file for APNS?
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Here is what I did, From:blog.boxedice.com and "iPhone Advanced Projects" chapter 10 byJoe Pezzillo.
With the aps_developer_identity.cer in the keychain:
Launch Keychain Access from your local Mac and from the login keychain, filter by the Certificates category. Yo...