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How to test if list element exists?
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This is actually a bit trickier than you'd think. Since a list can actually (with some effort) contain NULL elements, it might not be enough to check is.null(foo$a). A more stringent test might be to check that the name is actually defin...
Rename a dictionary key
... this question seems to be asking, is impractical because dict keys are usually immutable objects such as numbers, strings or tuples. Instead of trying to modify the key, reassigning the value to a new key and removing the old key is how you can achieve the "rename" in python.
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How to send a PUT/DELETE request in jQuery?
...ch as PUT and DELETE, can also be used here, but they are not supported by all browsers." from: api.jquery.com/jQuery.ajax/#options
– andilabs
Dec 2 '13 at 8:11
23
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Difference between doseq and for in Clojure
...e's answer is
(for [x [1 2 3]] (println x))
At the REPL, this will generally do what you want, but that's basically a coincidence: the REPL forces the lazy sequence produced by for, causing the printlns to happen. In a non-interactive environment, nothing will ever be printed. You can see this in...
Navigation in django
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I like this idea a lot, especially for flexibility, but it comes with the less-DRY trade-off. I did start using this in a site though.
– anonymous coward
Sep 22 '09 at 14:47
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Make the current commit the only (initial) commit in a Git repository?
...e using submodules, you should use e.g. interactive rebase
Step 1: remove all history (Make sure you have backup, this cannot be reverted)
cat .git/config # note <github-uri>
rm -rf .git
Step 2: reconstruct the Git repo with only the current content
git init
git add .
git commit -m "Init...
Can I pass an array as arguments to a method with variable arguments in Java?
...ompatibility.
So you should just be able to prepend extraVar to args and call String.format(format, args).
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How would one write object-oriented code in C? [closed]
What are some ways to write object-oriented code in C? Especially with regard to polymorphism.
32 Answers
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`static` keyword inside function?
...e value of the given variable ($has_run in your example) between multiple calls.
You could use this for different purposes, for example:
function doStuff() {
static $cache = null;
if ($cache === null) {
$cache = '%heavy database stuff or something%';
}
// code using $cache
}
In th...
Drawing Isometric game worlds
...loop with fairly straight forward logic that works consistently throughout all tiles.
Disadvantage:
One downside to that approach is that the x and y coordinates of the tiles on the map will increase in diagonal lines, which might make it more difficult to visually map the location on the screen t...