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See what has been installed via MacPorts
Is there a way to see all I have installed via MacPorts?
1 Answer
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JPA: unidirectional many-to-one and cascading delete
...e as ON DELETE CASCADE. You'll need to invoke EntityManager.clear() after calling EntityManager.remove(parent) as the persistence context needs to be refreshed - the child entities are not supposed to exist in the persistence context after they've been deleted in the database.
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How to convert C# nullable int to int
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The other answers so far are all correct; I just wanted to add one more that's slightly cleaner:
v2 = v1 ?? default(int);
Any Nullable<T> is implicitly convertible to its T, PROVIDED that the entire expression being evaluated can never result in...
Java synchronized method lock on object, or method?
... anyway. That's a bit misleading. Synchronizing on the method is functionally equivalent to having a synchronized (this) block around the body of the method. The object "this" doesn't become locked, rather the object "this" is used as the mutex and the body is prevented from executing concurrentl...
API vs. Webservice [closed]
...s don't necessarily use HTTP, but this is almost always the case and is usually assumed unless mentioned otherwise.
For examples of web services specifically, see SOAP, REST, and XML-RPC. For an example of another type of API, one written in C for use on a local machine, see the Linux Kernel API.
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Does IE9 support console.log, and is it a real function?
...native ECMAScript functions and objects do. This is the reason apply and call are undefined on those methods. In IE 9, most DOM objects were improved to inherit from native ECMAScript types. As the developer tools are considered an extension to IE (albeit, a built-in extension), they clearly didn...
Does anyone beside me just NOT get ASP.NET MVC? [closed]
...h greater control over the page output and a higher-level, more architecturally-driven approach. Let me capture Web Forms and MVC and show why I think that the comparison favors Web Forms in many situations - as long as you don't fall into some classic Web Forms traps.
Web Forms
In the Web Forms m...
Can virtual functions have default parameters?
... or a derived class' -- is determined by the static type used to make the call to the function. If you call through a base class object, pointer or reference, the default denoted in the base class is used. Conversely, if you call through a derived class object, pointer or reference the defaults de...
How can I find the location of origin/master in git, and how do I change it?
...ch master
master
Tracked remote branch
master
A remote is basically a link to a remote repository. When you do..
git remote add unfuddle me@unfuddle.com/myrepo.git
git push unfuddle
..git will push changes to that address you added. It's like a bookmark, for remote repositories.
When...
How to have click event ONLY fire on parent DIV, not children?
... a little complex). In this case, because objects are being compared, it really doesn't make a difference, but you'll find that most people will still stick with the strict comparison.
– user1106925
Jul 9 '15 at 18:26
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