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I tried to create a tag on SO that contained a plus character ("+"), but instead two seperate tags where used. How can I create a tag that contains "+"?

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My previous reply was wrong Sanoj, I apologize.. of course + is allowed, there are tags like c++. But you are right it doesn't let you create one. Weird. – Andreas Bonini Apr 3 '10 at 9:40
see… for why "++" works but "+" doesn't – quack quixote Apr 3 '10 at 12:38
Connect them with a hyphen. – kennytm Apr 3 '10 at 15:07
@KennyTM: I actually want a + for use in b+tree, because b-tree is something different. – Jonas Apr 4 '10 at 10:12
up vote 7 down vote accepted

b-tree is the tag for both, b-tree and b+ tree. You do not need an extra tag for it. You explain in your question that it is a b+ tree, that's sufficient.

No-one clicking with "oh, a b-tree question, I can answer this!" in mind will be scared away with "Aaaah, b+! The evil master! Run, run!" after reading the question text.

There are already several questions which do exactly that (using b-tree for b+ trees, not scaring their readers away).

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Fair enough, this is what I ended up with and did. – Jonas Apr 6 '10 at 18:01

@Sanoj wrote:
I actually want a + for use in b+tree, because b-tree is something different

Here's a workaround:


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this is what I recommend, if the distinction is so important. we don't allow plus in the middle of tags. – Jeff Atwood Jun 7 '10 at 8:59

You can't create tags with a plus in the middle, because .. well, just look:

is that questions tagged [b] and [tree]?

Incidentally, that's why when any tag contains a plus (we only allow it at the end) you must (and our system does) delimit tags in URLs with a space.

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That's not (no longer?) true. See c++11. – Mechanical snail Oct 27 '12 at 1:31

If you're creating new tags, you're probably doing something wrong. 99% of the time or more you should be using existing tags. It's extremely rare to have a question that covers a completely new topic area.

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I agree, but this is not an answer to my question. – Jonas Apr 6 '10 at 17:57

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