大约有 12,000 项符合查询结果（耗时：0.0312秒） [XML]
How to document a method with parameter(s)?
...s a compact, machine-readable syntax:
from typing import Dict, Union
def foo(i: int, d: Dict[str, Union[str, int]]) -> int:
"""
Explanation: this function takes two arguments: `i` and `d`.
`i` is annotated simply as `int`. `d` is a dictionary with `str` keys
and values that can ...
Will the Garbage Collector call IDisposable.Dispose for me?
...r this:
class Program
{
static void Main(string[] args)
{
Foo foo = new Foo();
foo = null;
Console.WriteLine("foo is null");
GC.Collect();
Console.WriteLine("GC Called");
Console.ReadLine();
}
}
class Foo : IDisposable
{
public void D...
Replace a value if null or undefined in JavaScript
... // false
// Equivalent to
a = a ?? true
Object/Array Examples
let x = ["foo"]
let y = { foo: "fizz" }
x[0] ??= "bar" // "foo"
x[1] ??= "bar" // "bar"
y.foo ??= "buzz" // "fizz"
y.bar ??= "buzz" // "buzz"
x // Array [ "foo", "bar" ]
y // Object { foo: "fizz", bar: "buzz" }
Functional Exa...
Is it better to use std::memcpy() or std::copy() in terms to performance?
... for a simple std::copy of a POD type.
#include <algorithm>
struct foo
{
int x, y;
};
void bar(foo* a, foo* b, size_t n)
{
std::copy(a, a + n, b);
}
Here's the disassembly (with only -O optimisation), showing the call to memmove:
bar(foo*, foo*, unsigned long):
salq $3, %r...
What does “export” do in shell programming? [duplicate]
...ssignment visible to subprocesses.
jcomeau@intrepid:~/rentacoder/bin2txt$ foo=bar
jcomeau@intrepid:~/rentacoder/bin2txt$ bash -c 'echo $foo'
jcomeau@intrepid:~/rentacoder/bin2txt$ export foo
jcomeau@intrepid:~/rentacoder/bin2txt$ bash -c 'echo $foo'
bar
...
JavaScript: How to pass object by value?
...ject.
var o = {};
(function(x){
var obj = Object.create( x );
obj.foo = 'foo';
obj.bar = 'bar';
})(o);
alert( o.foo ); // undefined
So any properties you add to obj will be not be added to o. Any properties added to obj with the same property name as a property in o will shadow the o...
Why can't I define a static method in a Java interface?
...have some classes that meet this requirement. How would you use it?
class Foo implements IXMLizable<Foo> {
public static Foo newInstanceFromXML(Element e) { ... }
}
Foo obj = Foo.newInstanceFromXML(e);
Since you have to explicitly name the concrete type Foo when "constructing" the new ob...
How to delete a file or folder?
...ling.
EXAMPLE for os.path.isfile
#!/usr/bin/python
import os
myfile="/tmp/foo.txt"
## If file exists, delete it ##
if os.path.isfile(myfile):
os.remove(myfile)
else: ## Show an error ##
print("Error: %s file not found" % myfile)
###Exception Handling
#!/usr/bin/python
import os
## Get...
Should a function have only one return statement?
...d to return for "easy" situations. For example, this:
public void DoStuff(Foo foo)
{
if (foo != null)
{
...
}
}
... can be made more readable (IMHO) like this:
public void DoStuff(Foo foo)
{
if (foo == null) return;
...
}
So yes, I think it's fine to have multiple ...
Where can I learn how to write C code to speed up slow R functions? [closed]
...examples. This function creates a character vector using the C API:
SEXP foobar(){
SEXP ab;
PROTECT(ab = allocVector(STRSXP, 2));
SET_STRING_ELT( ab, 0, mkChar("foo") );
SET_STRING_ELT( ab, 1, mkChar("bar") );
UNPROTECT(1);
}
Using Rcpp, you can write the same function as:
SEXP fooba...