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Best way to test for a variable's existence in PHP; isset() is clearly broken

... This looks a bit ugly to me, but in the case where you're actually checking an array element, it makes much more sense: isset($foo[$bar]) becomes array_key_exists($bar, $foo) – Arild Aug 25 '14 at 14:12 ...
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Timeout a command in bash without unnecessary delay

...y, Bash does not support floating point arithmetic (sleep does), therefore all delay/time values must be integers. EOF } # Options. while getopts ":t:i:d:" option; do case "$option" in t) timeout=$OPTARG ;; i) interval=$OPTARG ;; d) delay=$OPTARG ;; *) printUsage...
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Static nested class in Java, why?

...ike any other top-level class. In effect, a static nested class is behaviorally a top-level class that has been nested in another top-level class for packaging convenience. There is no need for LinkedList.Entry to be top-level class as it is only used by LinkedList (there are some other interface...
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Entity Framework: There is already an open DataReader associated with this Command

I am using Entity Framework and occasionally i will get this error. 17 Answers 17 ...
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How can I create a self-signed cert for localhost?

... I followed all these steps and I'm getting a ERR_SSL_VERSION_OR_CIPHER_MISMATCH in Chrome 60 and Safari 10.1.2 doesn't like it either. – styfle Aug 5 '17 at 21:19 ...
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What does .SD stand for in data.table in R

.SD looks useful but I do not really know what I am doing with it. What does it stand for? Why is there a preceding period (full stop). What is happening when I use it? ...
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Linq Query keeps throwing “Unable to create a constant value of type System.Object…”, Why?

...tBindingSource.Position = accountBindingSource.IndexOf(_dataService.Db.Accounts.First(ac => ac.AccountName == name)); accountBindingSource_CurrentChanged(sender, e); } buggy code: private void onTopAccBtnClick(object sender, EventArgs e) { accountBin...
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Can I use Twitter Bootstrap and jQuery UI at the same time?

... with jQuery UI (something which caused a number of widgets to break visually) The ability to theme jQuery UI widgets using Bootstrap styles. Whilst I love jQuery UI, I (like others) find some of the current themes to look a little dated. My hope is that this theme provides a decent alternat...
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Code equivalent to the 'let' keyword in chained LINQ extension method calls

...ime it's executed: var seq = EnumerableEx.Generate( new Random(), _ => true, _ => _, x => x.Next()); To see that new random samples show up every time, consider the following seq.Zip(seq, Tuple.Create).Take(3).Dump(); which produces pairs in which the left and right ar...
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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? ...