大约有 40,000 项符合查询结果（耗时：0.0470秒） [XML]
Extending from two classes
...ever I see a couple issues with it that would need to be addressed in more detail. First extending from two existing classes would be a bit more problematic and there would be a number of extra hurdles to go through, Second is if interface Foo and Bar both had the same functions, you would need to ...
Insert, on duplicate update in PostgreSQL?
...a lot. See why is upsert so complicated, which discusses this case in more detail.
This approach is also subject to lost updates in read committed isolation unless the application checks the affected row counts and verifies that either the insert or the update affected a row.
...
How do I run a node.js app as a background service?
...ou can get it back back doing screen -r. Hit up the screen manual for more details. You can name the screens and whatnot if you like.
share
|
improve this answer
|
follow
...
phpunit mock method multiple calls with different arguments
...ead to brittle tests which are too closely tied to specific implementation details.
Since 4.1 you can use withConsecutive eg.
$mock->expects($this->exactly(2))
->method('set')
->withConsecutive(
[$this->equalTo('foo'), $this->greaterThan(0)],
[$this-&...
Can I recover a branch after its deletion in Git?
...
@Philippe Thank you, for the very detailed explanation! thank you, works like a charm.
– Alex
May 11 at 23:48
...
When should the volatile keyword be used in C#?
...duce stronger
guarantees about observation of ordering. If you want more details,
read sections 3.10 and 10.5.3 of the C# 4.0 specification.
Frankly, I discourage you from ever making a volatile field. Volatile
fields are a sign that you are doing something downright crazy: you're
attem...
Creating a new user and password with Ansible
... for user module, it'll direct you to the Ansible-examples github repo for details how to use password parameter.
There you'll see that your password must be hashed.
- hosts: all
user: root
vars:
# created with:
# python -c 'import crypt; print crypt.crypt("This is my Password", "$1$So...
What does it mean to “program to an interface”?
...nderful answers on here to this questions that get into all sorts of great detail about interfaces and loosely coupling code, inversion of control and so on. There are some fairly heady discussions, so I'd like to take the opportunity to break things down a bit for understanding why an interface is...
When would anyone use a union? Is it a remnant from the C-only days?
...nrestricted in C++11. See the document linked to above or this article for details.
share
|
improve this answer
|
follow
|
...
Are Exceptions in C++ really slow
...he misses, and thus not trivial compared to pure CPU code.
Note: for more details, read the TR18015 report, chapter 5.4 Exception Handling (pdf)
So, yes, exceptions are slow on the exceptional path, but they are otherwise quicker than explicit checks (if strategy) in general.
Note: Andrei Alexand...