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Which is faster in Python: x**.5 or math.sqrt(x)?
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I've now run it 3 times on codepad.org and all three times a() was much faster than b().
– Jeremy Ruten
Nov 29 '08 at 1:38
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How can I cast int to enum?
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@FlySwat, what if YourEnum is dynamic and will only be known at runtime, and what I want is to convert to Enum?
– Shimmy Weitzhandler
Feb 19 '12 at 9:56
235
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Run a string as a command within a Bash script
...p -Eo '[[:digit:]]{4}[[:digit:]]{2}[[:digit:]]{2}')
echo $cmd
My output is now 20200824
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How does virtual inheritance solve the “diamond” (multiple inheritance) ambiguity?
...ally inherit A. D's object size is increased because it stores 2 pointers now; however there is only one A now.
So B::A and C::A are the same and so there can be no ambiguous calls from D. If you don't use virtual inheritance you have the second diagram above. And any call to a member of A the...
Callback after all asynchronous forEach callbacks are completed
...ilise Promises and Async/await feature. this solution would be obsolete by now.
– Emil Reña Enriquez
Sep 2 '19 at 19:31
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Get next / previous element using JavaScript?
...e a collection.
var divs = document.getElementsByTagName("div");
//divs now contain each and every div element on the page
var selectionDiv = document.getElementById("MySecondDiv");
So basically with selectionDiv iterate through the collection to find its index, and then obviously -1 = previous...
Using an image caption in Markdown Jekyll
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Jekyll now includes a site.url variable.
– Roy Tinker
Nov 14 '14 at 0:22
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PHP namespaces and “use”
...is equivalent to:
use My\Full\Namespace as Namespace;
// Namespace\Foo is now shorthand for My\Full\Namespace\Foo
If the use operator is used with a class or interface name, it has the following uses:
// after this, "new DifferentName();" would instantiate a My\Full\Classname
use My\Full\Classna...
C++ Object Instantiation
...a = new B();
a->f();
delete a;
return 0;
}
This will print "B". Now lets see what happens when using Stack:
int main(void) {
A a = B();
a.f();
return 0;
}
This will print "A", which might not be intuitive to those who are familiar with Java or other object oriented languages. The...
What is the difference between the 'COPY' and 'ADD' commands in a Dockerfile?
....gz DOES NOT EXTRACT the archive to the filesystem (I double checked right now to be sure and it's confirmed)
– Cecile
Oct 19 '18 at 15:19
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