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Evaluate empty or null JSTL c tags
...c:choose>
Or if you don't need to conditionally render a bunch of tags and thus you could only check it inside a tag attribute, then you can use the EL conditional operator ${condition? valueIfTrue : valueIfFalse}:
<c:out value="${empty var1 ? 'var1 is empty or null' : 'var1 is NOT empty or n...
Explaining Python's '__enter__' and '__exit__'
...nt.
The idea is that it makes it easy to build code which needs some 'cleandown' code executed (think of it as a try-finally block). Some more explanation here.
A useful example could be a database connection object (which then automagically closes the connection once the corresponding 'with'-sta...
Where does Vagrant download its .box files to?
What happens to the .box file after the following command is executed?
8 Answers
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How to run Rails console in the test environment and load test_helper.rb?
...ghtbot's "Factory Girl" gem, with is used to create objects to use in unit and other tests. I'd like to go to the console and run different Factory Girl calls to check out what's happening. For example, I'd like to go in there are do...
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How to drop a database with Mongoose?
I'm preparing a database creation script in Node.js and Mongoose.
How can I check if the database already exists, and if so, drop (delete) it using Mongoose?
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Email validation using jQuery
I'm new to jQuery and was wondering how to use it to validate email addresses.
35 Answers
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Xcode 4: How do you view the console?
...ight in left sidebar). Then choose your Debug/Run session in left sidebar, and you will have console in editor area.
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Editing legend (text) labels in ggplot
I have spent hours looking in the documentation and on StackOverflow, but no solution seems to solve my problem. When using ggplot I can't get the right text in the legend, even though it's in my dataframe. I have tried scale_colour_manual , scale_fill_manual with different values for labels=...
str performance in python
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'%s' % 100000 is evaluated by the compiler and is equivalent to a constant at run-time.
>>> import dis
>>> dis.dis(lambda: str(100000))
8 0 LOAD_GLOBAL 0 (str)
3 LOAD_CONST 1 (100000)
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How can I get form data with JavaScript/jQuery?
...rializeArray. It returns an array of arrays (which contain an entry "name" and "value") but that should be easy enough to transform.
– Bart van Heukelom
Feb 16 '10 at 21:33
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