大约有 12,000 项符合查询结果（耗时：0.0270秒） [XML]
Can I implement an autonomous `self` member type in C++?
...
Here's how you can do it without repeating the type of Foo:
template <typename...Ts>
class Self;
template <typename X, typename...Ts>
class Self<X,Ts...> : public Ts...
{
protected:
typedef X self;
};
#define WITH_SELF(X) X : public Self<X>
#define ...
Decorators with parameters?
...s.
One way of thinking about decorators with arguments is
@decorator
def foo(*args, **kwargs):
pass
translates to
foo = decorator(foo)
So if the decorator had arguments,
@decorator_with_args(arg)
def foo(*args, **kwargs):
pass
translates to
foo = decorator_with_args(arg)(foo)
de...
What's the _ underscore representative of in Swift References?
...by default don't have external parameter names.
For example, we have this foo() method defined in class Bar:
class Bar{
func foo(s1: String, s2: String) -> String {
return s1 + s2;
}
}
When you call foo(), it is called like bar.foo("Hello", s2: "World").
But, you can override...
What's the best way to inverse sort in scala?
...
Both sortWith and sortBy have a compact syntax:
case class Foo(time:Long, str:String)
val l = List(Foo(1, "hi"), Foo(2, "a"), Foo(3, "X"))
l.sortWith(_.time > _.time) // List(Foo(3,X), Foo(2,a), Foo(1,hi))
l.sortBy(- _.time) // List(Foo(3,X), Foo(2,a), Foo(1,hi))
l....
dynamic_cast and static_cast in C++
...tual void DoIt() = 0; // pure virtual
virtual ~Base() {};
};
class Foo : public Base
{
public:
virtual void DoIt() { cout << "Foo"; };
void FooIt() { cout << "Fooing It..."; }
};
class Bar : public Base
{
public :
virtual void DoIt() { cout << "Bar"; }
voi...
Remove all child elements of a DOM node in JavaScript
...ers may optimize for the case where the value is an empty string).
doFoo.onclick = () => {
const myNode = document.getElementById("foo");
myNode.innerHTML = '';
}
<div id='foo' style="height: 100px; width: 100px; border: 1px solid black;">
<span>Hello</span>
&l...
How to install gem from GitHub source?
...positories.
In your Gemfile:
# Use the http(s), ssh, or git protocol
gem 'foo', git: 'https://github.com/dideler/foo.git'
gem 'foo', git: 'git@github.com:dideler/foo.git'
gem 'foo', git: 'git://github.com/dideler/foo.git'
# Specify a tag, ref, or branch to use
gem 'foo', git: 'git@github.com:didel...
AngularJS : Differences among = & @ in directive scope? [duplicate]
...xplained ... if your directive looks like this:
<my-directive target="foo"/>
Then you have these possibilities for scope:
{ target : '=' }
This will bind scope.target (directive) to $scope.foo (outer scope). This is because = is for two-way binding and when you don't specify anything...
Difference between “and” and && in Ruby?
...ength, which can lead to peculiar behavior if you're not prepared for it:
foo = :foo
bar = nil
a = foo and bar
# => nil
a
# => :foo
a = foo && bar
# => nil
a
# => nil
a = (foo and bar)
# => nil
a
# => nil
(a = foo) && bar
# => nil
a
# => :foo
The same t...
Command not found error in Bash variable assignment
...
You cannot have spaces around your '=' sign.
When you write:
STR = "foo"
bash tries to run a command named STR with 2 arguments (the strings '=' and 'foo')
When you write:
STR =foo
bash tries to run a command named STR with 1 argument (the string '=foo')
When you write:
STR= foo
bas...