大约有 7,000 项符合查询结果（耗时：0.0271秒） [XML]
while (1) Vs. for (;;) Is there a speed difference?
... they result in the same opcodes:
$ perl -MO=Concise -e 'for(;;) { print "foo\n" }'
a <@> leave[1 ref] vKP/REFC ->(end)
1 <0> enter ->2
2 <;> nextstate(main 2 -e:1) v ->3
9 <2> leaveloop vK/2 ->a
3 <{> enterloop(next->8 last->9 red...
How do I look inside a Python object?
...
I'm surprised no one's mentioned help yet!
In [1]: def foo():
...: "foo!"
...:
In [2]: help(foo)
Help on function foo in module __main__:
foo()
foo!
Help lets you read the docstring and get an idea of what attributes a class might have, which is pretty helpful.
...
How can I split a JavaScript string by white space or comma?
... sooner or later you'll end up getting empty elements in the array. e.g. ['foo', '', 'bar'].
Which is fine if that's okay for your use case. But if you want to get rid of the empty elements you can do:
var str = 'whatever your text is...';
str.split(/[ ,]+/).filter(Boolean);
...
Operator overloading : member function vs. non-member function?
...s type appears on the right hand side of a binary operator. For example:
Foo f = 100;
int x = 10;
cout << x + f;
This only works if there is a global operator overload for
Foo operator + (int x, const Foo& f);
Note that the global operator overload doesn't necessarily need to be ...
How do I create a file AND any folders, if the folders don't exist?
Imagine I wish to create (or overwrite) the following file :- C:\Temp\Bar\Foo\Test.txt
9 Answers
...
Purpose of returning by const value? [duplicate]
...ion.
It's difficult to get it to have any effect on your code:
const int foo() {
return 3;
}
int main() {
int x = foo(); // copies happily
x = 4;
}
and:
const int foo() {
return 3;
}
int main() {
foo() = 4; // not valid anyway for built-in types
}
// error: lvalue required a...
Private module methods in Ruby
...Module.private_class_method, which arguably expresses more intent.
module Foo
def self.included(base)
base.instance_eval do
def method_name
# ...
end
private_class_method :method_name
end
end
end
For the code in the question:
module Thing
def self.pub; put...
Shell equality operators (=, ==, -eq)
...are equivalent, and in plain sh = is the only one guaranteed to work.
$ a=foo
$ [ "$a" = foo ]; echo "$?" # POSIX sh
0
$ [ "$a" == foo ]; echo "$?" # bash specific
0
$ [ "$a" -eq foo ]; echo "$?" # wrong
-bash: [: foo: integer expression expected
2
(Side note: Quote those variable ...
Does IMDB provide an API? [closed]
...lement('script'); s.src = src; document.head.appendChild(s); }
window.imdb$foo = function (results) {
/* ... */
};
addScript('https://sg.media-imdb.com/suggests/f/foo.json');
// 2) Using jQuery (JSON-P)
jQuery.ajax({
url: 'https://sg.media-imdb.com/suggests/f/foo.json',
dataType: 'jsonp',...
Cast to int vs floor
...e a new question.
Why do you think they will have the same result?
float foo = (int)(bar / 3.0) //will create an integer then assign it to a float
float foo = fabs(bar / 3.0 ) //will do the absolute value of a float division
bar = 1.0
foo1 = 0;
foo2 = 0.33333...
...