大约有 7,000 项符合查询结果（耗时：0.0188秒） [XML]
Why does C++11 not support designated initializer lists as C99? [closed]
...oat b;
};
What order would these functions be called in in c99: struct X foo = {.a = (char)f(), .b = g(), .c = h()}? Surprisingly, in c99:
The order of evaluation of the subexpressions in any initializer is indeterminately sequenced [1]
(Visual C++, gcc, and Clang seem to have an agreed upon...
delegate keyword vs. lambda notation
...ublic class Test
{
static void Main()
{
int x = 0;
Foo( () => x );
Foo( delegate { return x; } );
}
static void Foo(Func<int, int> action)
{
Console.WriteLine("I suspect the anonymous method...");
}
static void Foo(Expression<...
How to access the correct `this` inside a callback?
... (except for arrow functions, see below). Here are some examples:
function foo() {
console.log(this);
}
// normal function call
foo(); // `this` will refer to `window`
// as object method
var obj = {bar: foo};
obj.bar(); // `this` will refer to `obj`
// as constructor function
new foo(); // `...
Iterate over object attributes in python
...Assuming you have a class such as
>>> class Cls(object):
... foo = 1
... bar = 'hello'
... def func(self):
... return 'call me'
...
>>> obj = Cls()
calling dir on the object gives you back all the attributes of that object, including python special attributes...
How to assign a heredoc value to a variable in Bash?
...th this:
$ read -r -d '' VAR <<'EOF'
abc'asdf"
$(dont-execute-this)
foo"bar"''
EOF
If you don't quote the variable when you echo it, newlines are lost. Quoting it preserves them:
$ echo "$VAR"
abc'asdf"
$(dont-execute-this)
foo"bar"''
If you want to use indentation for readability in the...
DESTDIR and PREFIX of make
...all it to a different place but not create all the directories as DESTDIR=/foo/bar/baz would. It's commonly used with GNU stow via
./configure --prefix=/usr/local && make && sudo make install prefix=/usr/local/stow/foo
, which would install binaries in /usr/local/stow/foo/bin. By ...
What does java:comp/env/ do?
...work.jndi.JndiObjectFactoryBean">
<property name="jndiName" value="foo"/>
</bean>
Then you can access it directly using:
Context ctx = new InitialContext();
DataSource ds = (DataSource)ctx.lookup("java:comp/env/foo");
or you could make an intermediate step so you don't have to ...
Display filename before matching line
... That's important if you are using grep with find, like find . -name foo -exec grep pattern {} \; - assuming plenty of files named foo in your subdirectory, find still hands grep a single file to operate on at a time. The /dev/null trick seems to work in all linux/osx flavors that I've tried,...
Pointers in C: when to use the ampersand and the asterisk?
...ment, the function will receive a pointer, not an array:
int arr[10];
...
foo(arr);
...
void foo(int *arr) { ... }
This is why you don't use the & operator for arguments corresponding to "%s" in scanf():
char str[STRING_LENGTH];
...
scanf("%s", str);
Because of the implicit conversion, sc...
Query-string encoding of a Javascript Object
...p]));
}
return str.join("&");
}
console.log(serialize({
foo: "hi there",
bar: "100%"
}));
// foo=hi%20there&bar=100%25
Edit: this one also converts recursive objects (using php "array" notation for the query string)
serialize = function(obj, prefix) {
var s...