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Why would I ever use push_back instead of emplace_back?
...ncluding the version that ship with Visual Studio 2012, 2013 and 2015.
In order to accommodate known compiler bugs, prefer usingstd::vector::push_back() if the parameters reference iterators or other objects which will be invalid after the call.
std::vector<int> v;
v.emplace_back(123);
v.emp...
How to draw a rounded Rectangle on HTML Canvas?
...nt.getElementById("rounded-rect").getContext("2d");
// Draw using default border radius,
// stroke it but no fill (function's default values)
roundRect(ctx, 5, 5, 50, 50);
// To change the color on the rectangle, just manipulate the context
ctx.strokeStyle = "rgb(255, 0, 0)";
ctx.fillStyle = "rgba(...
Are global variables in PHP considered bad practice? If so, why?
...se that global variable, and not only that, you have to figure out in what order those references to the global variable are accessed.
If you have a global variable in a piece of code it makes it difficult to isolate the functionality of that code. Why would you want to isolate functionality? So yo...
mongodb group values by multiple fields
...lf-join" with another pipeline expression, in which we can apply $limit in order to return the "top-n" results.
db.books.aggregate([
{ "$group": {
"_id": "$addr",
"count": { "$sum": 1 }
}},
{ "$sort": { "count": -1 } },
{ "$limit": 2 },
{ "$lookup": {
"from": "books",
"let"...
Why is the minimalist, example Haskell quicksort not a “true” quicksort?
...cksort actually behaves in Haskell in terms of memory accesses or even the order of comparisons. If you could only observe the behavior, and not the source code, you would not recognize what it's doing as a quicksort.
For example, the C version of quicksort partitions all the data before the first ...
PowerShell script to return versions of .NET Framework on a machine?
...
If you're going to use the registry you have to recurse in order to get the full version for the 4.x Framework. The earlier answers both return the root number on my system for .NET 3.0 (where the WCF and WPF numbers, which are nested under 3.0, are higher -- I can't explain that), a...
How to pass a function as a parameter in Java? [duplicate]
...t of this post describes what we used to have to do in the bad old days in order to implement this functionality.
Typically you declare your method as taking some interface with a single method, then you pass in an object that implements that interface. An example is in commons-collections, where y...
How can I use Autolayout to set constraints on my UIScrollview?
..., Command click both the content view and the scroll view's parent view in order to select them both. Then set the heights to be equal (Control drag from the Content View to the Scroll View). This is also key. Because we are scrolling horizontally, the scroll view's content view won't know how high ...
Framework vs. Toolkit vs. Library [duplicate]
...amework embodies some abstract
design, with more behavior built in.
In order to use it you need to insert
your behavior into various places in
the framework either by subclassing or
by plugging in your own classes. The
framework's code then calls your code
at these points.
To summari...
Should I use JSLint or JSHint JavaScript validation? [closed]
...documentation: says "You can also use ternary evaluations in free space in order to do different operations". developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/… @AuthorProxy I'm going for Mozilla and ignoring JSHint. Sorry.
– dewd
Apr 24 '15 at 14:52...