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I want to get the type of a variable at runtime
...y is that you want to reify the type of the variable. That is, you want to convert the type into a value, so you can store it, pass it around, etc. This involves reflection, and you'll be using either ClassTag or a TypeTag. For example:
val x: Any = 5
import scala.reflect.ClassTag
def f[T](v: T)(im...
Tags for Emacs: Relationship between etags, ebrowse, cscope, GNU Global and exuberant ctags
...t's page) cscope allows you to:
Go to the declaration of a symbol
Show a selectable list of all references to a symbol
Search for any global definition
Functions called by a function
Functions calling a function
Search for a text string
Search for a regular expression pattern
Find a file
Find all ...
John Carmack's Unusual Fast Inverse Square Root (Quake III)
... // gives initial guess y0
x = *(float*)&i; // convert bits back to float
x = x * (1.5f - xhalf * x * x); // Newton step, repeating increases accuracy
return x;
}
In spite of this, his initial attempt a mathematically 'superior' version of id's sqrt (which came ...
How do I get the computer name in .NET
... new ManagementObjectSearcher("root\\CIMV2",
"SELECT Name FROM Win32_ComputerSystem");
foreach (ManagementObject queryObj in searcher.Get())
{
Console.WriteLine("-----------------------------------");
Console.Write...
Compiled vs. Interpreted Languages
...r doesn't "learn" anything from having seen the line before, the effort of converting human-readable language to machine instructions is incurred every time for every line, so it's dog slow. On the bright side, the user can inspect and otherwise interact with his program in all kinds of ways: Changi...
How to avoid variable substitution in Oracle SQL Developer with 'trinidad & tobago'
...| ' Tobago');
insert into table99 values('Trinidad &' || ' Tobago');
SELECT * FROM table99;
update table99 set col1 = 'Trinidad and Tobago' where col1 = 'Trinidad &'||' Tobago';
share
|
...
How do I clear the terminal screen in Haskell?
How can I clear a terminal screen after my user has selected an option from my application's menu?
8 Answers
...
Understanding slice notation
...mber is that the :stop value represents the first value that is not in the selected slice. So, the difference between stop and start is the number of elements selected (if step is 1, the default).
The other feature is that start or stop may be a negative number, which means it counts from the end o...
Is it possible to clone html element objects in JavaScript / JQuery?
...od:
// Create a clone of element with id ddl_1:
let clone = document.querySelector('#ddl_1').cloneNode( true );
// Change the id attribute of the newly created element:
clone.setAttribute( 'id', newId );
// Append the newly created element on element p
document.querySelector('p').appendChild( cl...
Why '&&' and not '&'?
...if you translate true to 1 and false to 0, then do bitwise operation, then convert non-zero to true and zero to false; it happens that the result will be the same had you just used logical operator (check this for exercise).
Another important distinction is also that a logical operator is short-cir...