大约有 7,000 项符合查询结果（耗时：0.0253秒） [XML]
How can I reliably determine the type of a variable that is declared using var at design time?
... type of a particular expression inside a method body -- say you've typed "foo." and we need to figure out what are the members of foo -- we do the same thing; we skip as much work as we reasonably can.
We start with a pass which analyzes only the local variable declarations within that method. W...
Error message Strict standards: Non-static method should not be called statically in php
...en the respective function or variable should be declared as static
class Foo {
//Static variable
public static $static_var = 'static variable';
//Static function
static function staticValue() { return 'static function'; }
//function
function V...
When to use RSpec let()?
...I prefer this to one large before hook containing all of this. Also, let(:foo) { Foo.new } is less noisy (and more to the point) then before(:each) { @foo = Foo.new }. Here's an example of how I use it: github.com/myronmarston/vcr/blob/v1.7.0/spec/vcr/util/…
– Myron Marston...
Check variable equality against a list of values
I'm checking a variable, say foo , for equality to a number of values. For example,
13 Answers
...
How can you iterate over the elements of an std::tuple?
...t;boost/hana.hpp>
#include <boost/hana/ext/std/tuple.hpp>
struct Foo1 {
int foo() const { return 42; }
};
struct Foo2 {
int bar = 0;
int foo() { bar = 24; return bar; }
};
int main() {
using namespace std;
using boost::hana::for_each;
Foo1 foo1;
Foo2 foo2;
...
StringUtils.isBlank() vs String.isEmpty()
...
StringUtils.isBlank() will also check for null, whereas this:
String foo = getvalue("foo");
if (foo.isEmpty())
will throw a NullPointerException if foo is null.
share
|
improve this answer
...
Hashing a dictionary?
... However, here is one issue I found with hash, as regards objects:
class Foo(object): pass
foo = Foo()
print (hash(foo)) # 1209812346789
foo.a = 1
print (hash(foo)) # 1209812346789
The hash is the same, even after I've altered foo. This is because the identity of foo hasn't changed, so the hash...
How to filter rows in pandas by regex
...lready a string handling function Series.str.startswith().
You should try foo[foo.b.str.startswith('f')].
Result:
a b
1 2 foo
2 3 fat
I think what you expect.
Alternatively you can use contains with regex option. For example:
foo[foo.b.str.contains('oo', regex= True, na=False)...
What is the difference between 'E', 'T', and '?' for Java generics?
... wildcard which is used when providing a type argument, e.g. List<?> foo = ... means that foo refers to a list of some type, but we don't know what.
All of this is generics, which is a pretty huge topic. You may wish to learn about it through the following resources, although there are more a...
What does 'const static' mean in C and C++?
...n other forums. My best guess is that it's used in C to hide the constant foo from other modules. Is this correct? If so, why would anyone use it in a C++ context where you can just make it private ?
...