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Check if event exists on element [duplicate]
Is there a way to check if an event exists in jQuery? I’m working on a plugin that uses custom namespaced events, and would like to be able to check if the event is binded to an element or not.
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XPath to find elements that does not have an id or class
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That will give you all tr elements lacking both id and class attributes. If you want all tr elements lacking one of the two, use or instead of and:
//tr[not(@id) or not(@class)]
When attributes and elements are used in this way, if the attribute or element has a value it is treated as if it's t...
Using an if statement to check if a div is empty
I'm trying to remove a specific div if a separate div is empty. Here's what I'm using:
10 Answers
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How to write loop in a Makefile?
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The following will do it if, as I assume by your use of ./a.out, you're on a UNIX-type platform.
for number in 1 2 3 4 ; do \
./a.out $$number ; \
done
Test as follows:
target:
for number in 1 2 3 4 ; do \
echo $$number ; \
do...
Maven Install on Mac OS X
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OS X prior to Mavericks (10.9) actually comes with Maven 3 built in.
If you're on OS X Lion, you won't have java installed by default. Just run java by itself and it'll prompt you to install it.
Assuming qualifications are met, run mvn -version and see some output like this:
Apache Maven 3....
How to redirect output to a file and stdout
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The command you want is named tee:
foo | tee output.file
For example, if you only care about stdout:
ls -a | tee output.file
If you want to include stderr, do:
program [arguments...] 2>&1 | tee outfile
2>&1 redirects channel 2 (stderr/standard error) into channel 1 (stdout/s...
Delete/Reset all entries in Core Data?
...ntity is both slower and prone to error. The use for doing it that way is if you want to delete some entities and not others. However you still need to make sure you retain referential integrity or you won't be able to persist your changes.
Just removing the store and recreating it is both fast a...
When to add what indexes in a table in Rails
...unique)" to the automatically created "id" column?
No, same as above
If I add index to two foreign keys at once (add_index (:users, [:category_id, :state_id]), what happens? How is this different from adding the index for each key?
Then the index is a combined index of the two columns. That ...
Simple way to find if two different lists contain exactly the same elements?
What is the simplest way to find if two Lists contain exactly the same elements, in the standard Java libraries?
16 Answer...
iOS: Use a boolean in NSUserDefaults
...ults standardUserDefaults] synchronize];
and read it by using this code:
if(![[NSUserDefaults standardUserDefaults] boolForKey:@"logged_in"]) {
[self displayLogin];
} else {
[self displayMainScreen];
}
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