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Why is Scala's immutable Set not covariant in its type?
EDIT : Re-written this question based on original answer
3 Answers
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Entity Framework rollback and remove bad migration
I'm using EF 6.0 for my project in C# with manual migrations and updates. I have about 5 migrations on the database, but I realised that the last migration was bad and I don't want it. I know that I can rollback to a previous migration, but when I add a new (fixed) migration and run Update-Database,...
Sending and Receiving SMS and MMS in Android (pre Kit Kat Android 4.4)
...d the exact same problem you describe above (Galaxy Nexus on t-mobile USA) it is because mobile data is turned off.
In Jelly Bean it is:
Settings > Data Usage > mobile data
Note that I have to have mobile data turned on PRIOR to sending an MMS OR receiving one. If I receive an MMS with mobil...
Does the default constructor initialize built-in types?
Does the default constructor (created by the compiler) initialize built-in-types?
7 Answers
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How do I hide .class files from the Open Resource dialog in Eclipse?
I won't want to have edit any working sets. I just want a way to, across all workspaces and projects, prevent .class files from ever showing in the Open Resource Dialog. Is there a way to do this?
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Error Code: 1005. Can't create table '…' (errno: 150)
...Code: 1005 -- there is a wrong primary key reference in your code
Usually it's due to a referenced foreign key field that does not exist. It might be you have a typo mistake, or check case it should be same, or there's a field-type mismatch. Foreign key-linked fields must match definitions exactly....
What is the default access specifier in Java?
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The default visibility is known as “package-private” (though you can't use this explicitly), which means the field will be accessible from inside the same package to which the class belongs.
As mdma pointed out, it isn't true for interface...
Pushing an existing Git repository to SVN
I've been doing all my work in Git and pushing to GitHub. I've been very happy with both the software and the site, and I have no wish to change my working practices at this point.
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Difference between using Throwable and Exception in a try catch
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By catching Throwable it includes things that subclass Error. You should generally not do that, except perhaps at the very highest "catch all" level of a thread where you want to log or otherwise handle absolutely everything that can go wrong. It ...
How to escape a JSON string to have it in a URL?
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It seems though that it encodes more characters than necessary (when I paste the link in Firefox, some characters are reverted back (i.e. {["). Is there a way to encode only the characters necessary, so that I can shorten my ...