大约有 40,000 项符合查询结果（耗时：0.0553秒） [XML]
Uninstall old versions of Ruby gems
I have several versions of a Ruby gem:
6 Answers
6
...
Why does changing the returned variable in a finally block not change the return value?
...value of s at the time the return statement executes is the value returned by the method. The fact that the finally clause later changes the value of s (after the return statement completes) does not (at that point) change the return value.
Note that the above deals with changes to the value of s it...
Is returning null bad design? [closed]
...r one pointers to objects. (That's certainly how it's explicitly modelled by Haskell's Maybe in those cases, and is all the better for doing so.)
– Andrzej Doyle
Aug 6 '12 at 14:37
...
How to prevent that the password to decrypt the private key has to be entered every time when using
... '~' refers to your "home directory". In Windows, you can find this by opening a command shell (cmd) and typing "echo %USERPROFILE%".
– Hawkeye Parker
Aug 28 '12 at 23:56
14...
Check whether a string contains a substring
...es are needed because a . can match any character. You can get around this by using the \Q and \E operators.
my $substring = "s1.domain.com";
if ($mystring =~ /\Q$substring\E/) {
print qq("$mystring" contains "$substring"\n);
}
Or, you can do as eugene y stated and use the index function. ...
Re-raise exception with a different type and message, preserving existing information
...ueError("Bad grape") from exc
The caught exception (exc, a KeyError) thereby becomes part of (is the “cause of”) the new exception, a ValueError. The “cause” is available to whatever code catches the new exception.
By using this feature, the __cause__ attribute is set. The built-in exceptio...
Rails 3 datatypes?
...
and :references for polymorphic associations. See: api.rubyonrails.org/classes/ActiveRecord/ConnectionAdapters/…
– Ethan
Jan 25 '12 at 8:46
...
Why does installing Nokogiri on Mac OS fail with libiconv is missing?
...er. If you already have it installed, be sure to grab the latest formulae by updating like so:
brew update
Note: In OSX 10.9+ you may need to install xCode command tools to allow you to install libiconv.
xcode-select --install
then install a newer version of libiconv
brew install libiconv
...
ASP.NET MVC Controller Naming Pluralization
... single or multiple entities. Especially since the controller name is used by default in the URL.
While the project templates use singular (HomeController, AccountController), there is only one Home and the Account actions only operate on the single account for the session. I would not expect the U...
SQL ON DELETE CASCADE, Which Way Does the Deletion Occur?
...Here is a simple example for others visting this old post, but is confused by the example in the question:
Delivery -> Package (One -> Many)
CREATE TABLE Delivery(
Id INT IDENTITY PRIMARY KEY,
NoteNumber NVARCHAR(255) NOT NULL
)
CREATE TABLE Package(
Id INT IDENTITY PRIMARY KEY,...