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nodejs how to read keystrokes from stdin

... @Plentybinary I suspect you aren't actually running node v0.10.25. I tested this against v0.10.25 and it works properly. and process.stdin.setRawMode exists, is a function, and works properly. I also tested on iojs-2.3.1 and it still works there as well. – Peter Lyons ...
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html5 - canvas element - Multiple layers

...(ctx) are off screen. The image has been previously rendered onto ctx3. In test 1 of this benchmark, I directly render ctx3 onto ctx1. In test 2, I render ctx3 onto ctx2 and then ctx2 to ctx1. Test 2 is 30 times slower than test 1 on my computer. That is why I say using a intermediate canvas is much...
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Javascript - How to detect if document has loaded (IE 7/Firefox 3)

...alambalazs. The cross-browser way to do it in pure JavaScript is simply to test document.readyState: if (document.readyState === "complete") { init(); } This is also how jQuery does it. Depending on where the JavaScript is loaded, this can be done inside an interval: var readyStateCheckInterval...
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What does if __name__ == “__main__”: do?

...e is a library, but you want to have a script mode where it runs some unit tests or a demo. Your module is only used as a main program, but it has some unit tests, and the testing framework works by importing .py files like your script and running special test functions. You don't want it to try ru...
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Does async(launch::async) in C++11 make thread pools obsolete for avoiding expensive thread creation

...s under the impression that Linux thread creation was very cheap and after testing I determined that the overhead of function call in a new thread vs. a normal one is enormous. The overhead for creating a thread to handle a function call is something like 10000 or more times slower than a plain func...
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Optimise PostgreSQL for fast testing

... First, always use the latest version of PostgreSQL. Performance improvements are always coming, so you're probably wasting your time if you're tuning an old version. For example, PostgreSQL 9.2 significantly improves the speed of TRUNCATE and of cou...
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Find first element by predicate

...ns return a lazy stream). To convince you, you can simply do the following test: List<Integer> list = Arrays.asList(1, 10, 3, 7, 5); int a = list.stream() .peek(num -> System.out.println("will filter " + num)) .filter(x -> x > 5) .findFirst() ...
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Downloading an entire S3 bucket?

...ucket to the current directory. And will output: download: s3://mybucket/test.txt to test.txt download: s3://mybucket/test2.txt to test2.txt This will download all of your files using a one-way sync. It will not delete any existing files in your current directory unless you specify --delete, an...
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Create folder with batch but only if it doesn't already exist

...e a directory only if the folder does not exist. Note that this existence test will return true only if VTS exists and is a directory. If it is not there, or is there as a file, the mkdir command will run, and should cause an error. You might want to check for whether VTS exists as a file as well...
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How to parse JSON data with jQuery / JavaScript?

...Parsed); Then you can iterate the following: var j ='[{"id":"1","name":"test1"},{"id":"2","name":"test2"},{"id":"3","name":"test3"},{"id":"4","name":"test4"},{"id":"5","name":"test5"}]'; ...by using $().each: var json = $.parseJSON(j); $(json).each(function (i, val) { $.each(val, function (k...