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Unique fields that allow nulls in Django
...oo which has field bar. The bar field should be unique, but allow nulls in it, meaning I want to allow more than one record if bar field is null , but if it is not null the values must be unique.
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CSS fixed width in a span
Within an unordered list:
11 Answers
11
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Is there a standard naming convention for git tags? [closed]
...een a lot of projects using v1.2.3 as the naming convention for tags in git. I've also seen some use 1.2.3 . Is there an officially endorsed style, or are there any good arguments for using either?
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Can I “multiply” a string (in C#)?
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And it's not much more in .NET 3.5: String.Concat(Enumerable.Repeat("Hello", 4).ToArray())
– Mark Foreman
Sep 3 '12 at 0:54
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Hide the cursor of an UITextField
I am using a UITextField with a UIPickerView for its inputView , so that when the user taps the text field, a picker is summoned for them to select an option from.
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How can I trim beginning and ending double quotes from a string?
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You can use String#replaceAll() with a pattern of ^\"|\"$ for this.
E.g.
string = string.replaceAll("^\"|\"$", "");
To learn more about regular expressions, have al ook at http://regular-expression.info.
That said, this smells a bit like that you're try...
Write a function that returns the longest palindrome in a given string
I thought of a solution but it runs in O(n^2) time
22 Answers
22
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Remove elements from collection while iterating
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Let me give a few examples with some alternatives to avoid a ConcurrentModificationException.
Suppose we have the following collection of books
List<Book> books = new ArrayList<Book>();
books.add(new Book(new ISBN("0-201-63361-2")));
books...
How to overlay one div over another div
I need assistance with overlaying one individual div over another individual div .
8 Answers
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Git push won't do anything (everything up-to-date)
I'm trying to update a Git repository on GitHub. I made a bunch of changes, added them, committed then attempted to do a git push . The response tells me that everything is up to date, but clearly it's not.
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