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Performance difference for control structures 'for' and 'foreach' in C#
...get:
list[0]; // head
list[1]; // head.Next
list[2]; // head.Next.Next
// etc.
When you call GetEnumerator (implicitly using the forach-syntax), you'll get an IEnumerator object that has a pointer to the head node. Each time you call MoveNext, that pointer is moved to the next node, like so:
IEn...
JPA: How to have one-to-many relation of the same Entity type
... Collection<A> children;
// Getters, Setters, serialVersionUID, etc...
}
Here's a rough main() method that persists three such entities:
public static void main(String[] args) {
EntityManager em = ... // from EntityManagerFactory, injection, etc.
em.getTransaction().begin();
...
Is it good practice to make the constructor throw an exception? [duplicate]
... recover. Ex. An object constructor loads test data (usernames, passwords, etc.) from a config file. All tests then use the data in config object. Exceptions can be thrown if the file can't be found, data is in wrong format etc. I think the only way we can recover from the exceptions is by making a ...
How do I use valgrind to find memory leaks?
...all Valgrind on your system.
sudo apt install valgrind # Ubuntu, Debian, etc.
sudo yum install valgrind # RHEL, CentOS, Fedora, etc.
Valgrind is readily usable for C/C++ code, but can even be used for other
languages when configured properly (see this for Python).
To run Valgrind, pass the ex...
When do I need to use Begin / End Blocks and the Go keyword in SQL Server?
... all in one block.
BEGIN and END are just like { and } in C/++/#, Java, etc.
They bound a logical block of code. I tend to use BEGIN and END at the start and end of a stored procedure, but it's not strictly necessary there. Where it IS necessary is for loops, and IF statements, etc, where you ...
CMake output/build directory
...relative to CMAKE_BINARY_DIR, CMAKE_CURRENT_BINARY_DIR, PROJECT_BINARY_DIR etc.
If you look at CMake documentation, you'll see variables partitioned into semantic sections. Except for very special circumstances, you should treat all those listed under "Variables that Provide Information" as read-on...
ASP.NET MVC View Engine Comparison
...lisense
Compiled views
Extensibility using regular CLR classes, functions, etc
Seamless composability and manipulation since it's regular VB.NET code
Unit testable
Cons:
Performance: Builds the whole DOM before sending it to client.
Example:
Protected Overrides Function Body() As XElement
...
Zoom in on a point (using scale and translate)
...
var canvas = document.getElementById("canvas");
var context = canvas.getContext("2d");
var width = 600;
var height = 200;
var scale = 1;
var originx = 0;
var originy = 0;
var visibleWidth = width;
var visibleHeight = height;
function draw(){
// Clear screen to white.
con...
Code-first vs Model/Database-first [closed]
... that features like stored procedures mapping, query views, defining views etc. works when using Model/Database first and DbContext (I haven't tried it yet) but they don't in Code first.
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C++ auto keyword. Why is it magic?
...w people still write code for MS-DOS using compilers from Borland, Watcom, etc., that haven't seen significant upgrades in decades). If you're using a reasonably current version of any of the mainstream compilers, there's no reason to avoid it at all though.
...