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Why is Go so slow (compared to Java)?
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The 6g and 8g compilers are not particularly optimising, so the code they produce isn't particularly fast.
They're designed to run fast themselves and produce code that's OK (there is a bit of optimisation). gccgo uses GCC's existi...
Why does sys.exit() not exit when called inside a thread in Python?
...a stupid question, but I'm testing out some of my assumptions about Python and I'm confused as to why the following code snippet would not exit when called in the thread, but would exit when called in the main thread.
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Why is there no GIL in the Java Virtual Machine? Why does Python need one so bad?
...t need a GIL (which is why it can perfectly be implemented on JVM [Jython] and .NET [IronPython], and those implementations multithread freely). CPython (the popular implementation) has always used a GIL for ease of coding (esp. the coding of the garbage collection mechanisms) and of integration of ...
Cannot use ref or out parameter in lambda expressions
...ld need to be visible on the ref parameter itself. Both within the method and in the caller.
These are somewhat incompatible properties and are one of the reasons they are disallowed in lambda expressions.
share
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Why is rbindlist “better” than rbind?
I am going through documentation of data.table and also noticed from some of the conversations over here on SO that rbindlist is supposed to be better than rbind .
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How do I convert a byte array to Base64 in Java?
...deFromString(encoded);
println(new String(decoded)) // Outputs "Hello"
Android (with Java < 8)
If you are using the Android SDK before Java 8 then your best option is to use the bundled android.util.Base64.
For direct byte arrays:
byte[] encoded = Base64.encode("Hello".getBytes());
println(ne...
Why is document.body null in my javascript?
... that uses body. Not cool.
You want to wrap this code in a window.onload handler or place it after the <body> tag (as mentioned by e-bacho 2.0).
<head>
<title>Javascript Tests</title>
<script type="text/javascript">
window.onload = function() {
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Why does 'continue' behave like 'break' in a Foreach-Object?
...let (it even has the alias foreach that helps to make this conversion easy and make mistakes easy, too). All continues should be replaced with return.
P.S.: Unfortunately, it is not that easy to simulate break in ForEach-Object.
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“Debug only” code that should run only when “turned on”
...e here gets executed only when compiled with the DEBUG constant,
// and when the person debugging manually sets the bool above to true.
// It then stays for the rest of the session until they set it to false.
}
#endif
// ...
}
Just to be complete, pragmas (preprocessor directives...
How to sort a list in Scala by two fields?
...ort a list in Scala by two fields, in this example I will sort by lastName and firstName?
4 Answers
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