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Evaluate expression given as a string
...ss("5+5")
[1] "character"
> class(parse(text="5+5"))
[1] "expression"
Calling eval() invokes many behaviours, some are not immediately obvious:
> class(eval(parse(text="5+5")))
[1] "numeric"
> class(eval(parse(text="gray")))
[1] "function"
> class(eval(parse(text="blue")))
Error in ev...
Bytecode features not available in the Java language
...r, here is a summary of my findings:
Execute code in a constructor before calling a super constructor or auxiliary constructor
In the Java programming language (JPL), a constructor's first statement must be an invocation of a super constructor or another constructor of the same class. This is not ...
Two inline-block, width 50% elements wrap to second line [duplicate]
I would like to have two columns of 50% width space, and avoid floats.
So i thought using display:inline-block .
5 Answers...
setuptools vs. distutils: why is distutils still a thing?
...not included in the standard library. It introduced a command-line utility called easy_install. It also introduced the setuptools Python package that can be imported in your setup.py script, and the pkg_resources Python package that can be imported in your code to locate data files installed with a ...
Is pass-by-value a reasonable default in C++11?
... do this:
void foo(T t)
{
// ...
}
which has the advantage that the caller can use foo like so:
T lval;
foo(lval); // copy from lvalue
foo(T {}); // (potential) move from prvalue
foo(std::move(lval)); // (potential) move from xvalue
and only minimal work is done. You'd need two overloads t...
How to call Stored Procedure in Entity Framework 6 (Code-First)?
...
You can call a stored procedure in your DbContext class as follows.
this.Database.SqlQuery<YourEntityType>("storedProcedureName",params);
But if your stored procedure returns multiple result sets as your sample code, then yo...
Remove CSS class from element with JavaScript (no jQuery) [duplicate]
...
The right and standard way to do it is using classList. It is now widely supported in the latest version of most modern browsers:
ELEMENT.classList.remove("CLASS_NAME");
remove.onclick = () => {
const el = document.querySelector('#el');
if (el.classList.contains("red")) {
...
What are C++ functors and their uses?
...(42); // create an instance of the functor class
int i = add42(8); // and "call" it
assert(i == 50); // and it added 42 to its argument
std::vector<int> in; // assume this contains a bunch of values)
std::vector<int> out(in.size());
// Pass a functor to std::transform, which calls the f...
Adding div element to body or document in JavaScript
...
Try this out:-
http://jsfiddle.net/adiioo7/vmfbA/
Use
document.body.innerHTML += '<div style="position:absolute;width:100%;height:100%;opacity:0.3;z-index:100;background:#000;"></div>';
instead of
document.body.innerHTML = '<div...
Calling Python in Java?
I am wondering if it is possible to call python functions from java code using jython, or is it only for calling java code from python?
...