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How Big can a Python List Get?
...ognize them because of the asterix at the end) . Pointers are 4 bytes long and store a memory address to the allocated object. They are "only" 4 bytes long because with 4 bytes you can address every element in a memory of nowadays computers.
– Antonio Ragagnin
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How do I perform the SQL Join equivalent in MongoDB?
...t array field>
}
}
Of course Mongo is not a relational database, and the devs are being careful to recommend specific use cases for $lookup, but at least as of 3.2 doing join is now possible with MongoDB.
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How to concatenate two strings in C++?
...e performance. Worst case is, that operator+= performs both a deallocation and an allocation. Heap allocations are among the most expensive operations we commonly do.
– IInspectable
Feb 7 at 12:17
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How can I catch a ctrl-c event?
...;stdlib.h>
#include <stdio.h>
#include <unistd.h>
void my_handler(int s){
printf("Caught signal %d\n",s);
exit(1);
}
int main(int argc,char** argv)
{
struct sigaction sigIntHandler;
sigIntHandler.sa_handler = my_handler;
sigemptyset(&sigIntHand...
How can I select rows with most recent timestamp for each key value?
I have a table of sensor data. Each row has a sensor id, a timestamp, and other fields. I want to select a single row with latest timestamp for each sensor, including some of the other fields.
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How does JavaScript .prototype work?
...e code you write. The square brackets around [[Prototype]] are deliberate, and are an ECMAScript specification convention to denote internal slots.
The value pointed at by the [[Prototype]] of an object, is colloquially known as "the prototype of that object."
If you access a property via the do...
jQuery validate: How to add a rule for regular expression validation?
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this is super useful and should be included in jquery :(
– Grahame A
Aug 5 '11 at 19:47
3
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Convert a Python list with strings all to lowercase or uppercase
... python function that can convert all the strings in one pass to lowercase and vice versa, uppercase?
13 Answers
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Must qualify the allocation with an enclosing instance of type GeoLocation
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Another option, and the one I prefer, would be to set the inner class to be static.
public static class ThreadTask implements Runnable { ... }
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Enterprise app deployment doesn't work on iOS 7.1
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I found the issue by connecting the iPad to the computer and viewing the console through the XCode Organizer while trying to install the app. The error turns out to be:
Could not load non-https manifest URL: http://example.com/manifest.plist
Turns out that in iOS 7.1, the URL...