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Empty arrays seem to equal true and false at the same time

... You're testing different things here. if (arr) called on object (Array is instance of Object in JS) will check if the object is present, and returns true/false. When you call if (arr == false) you compare values of this object and the primitive false value. Internally, a...
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Can I install Python 3.x and 2.x on the same Windows computer?

I'm running Windows and the shell/OS automatically runs Python based on the registry settings when you run a program on the command line. Will this break if I install a 2.x and 3.x version of Python on the same machine? ...
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Checking if all elements in a list are unique

What is the best way (best as in the conventional way) of checking whether all elements in a list are unique? 14 Answers ...
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What's the state of the art in email validation for Rails?

... answered Aug 24 '10 at 9:56 HallelujahHallelujah 77466 silver badges44 bronze badges ...
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can we use xpath with BeautifulSoup?

...thon2, but Python3 is much preferred as 2 is being sunset (no longer officially supported) in 2020. – wordsforthewise Sep 30 '19 at 18:59 ...
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How do I instantiate a Queue object in java?

...n't want to do this, but it's listed as an option for the sake of covering all the bases. new Queue<Tree>() { public Tree element() { ... }; public boolean offer(Tree element) { ... }; ... }; ...
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Rails: How to change the text on the submit button in a Rails Form

... If you want to change all create and update form submit tags, this change is easy to make. Modify config/locales/en.yml like so: en: helpers: submit: create: "Crear un %{model}" update: "Confirmar cambios al %{model} creado" ...
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How to replace a character by a newline in Vim

...s a newline (more precisely, it’s treated as the input CR). Here’s a small, non-interactive example to illustrate this, using the Vim command line feature (in other words, you can copy and paste the following into a terminal to run it). xxd shows a hexdump of the resulting file. echo bar > te...
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Remove specific commit

...hanged line 2" 1 files changed, 1 insertions(+), 1 deletions(-) Then it all works as expected. The second answer was very interesting. There is a feature which has not yet been officially released (though it is available in Git v1.7.2-rc2) called Revert Strategy. You can invoke git like this: ...
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What is a semaphore?

...s bouncers at a nightclub. There are a dedicated number of people that are allowed in the club at once. If the club is full no one is allowed to enter, but as soon as one person leaves another person might enter. It's simply a way to limit the number of consumers for a specific resource. For exampl...