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Why is it faster to check if dictionary contains the key, rather than catch the exception in case it
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On the one hand, throwing exceptions is inherently expensive, because the stack has to be unwound etc.
On the other hand, accessing a value in a dictionary by its key is cheap, because it's a fast, O(1) operation.
BTW: The correct way t...
Check if event exists on element [duplicate]
...s in jQuery? I’m working on a plugin that uses custom namespaced events, and would like to be able to check if the event is binded to an element or not.
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What's the best way to iterate over two or more containers simultaneously
...ften in your data, consider using another pattern which zips two sequences and produces a range of tuples, corresponding to the paired elements:
for (auto& [a, b] : zip(containerA, containerB)) {
a = b;
}
The implementation of zip is left as an exercise for the reader, but it follows easi...
Define all functions in one .R file, call them from another .R file. How, if possible?
...If abc.R is:
fooABC <- function(x) {
k <- x+1
return(k)
}
and xyz.R is:
fooXYZ <- function(x) {
k <- fooABC(x)+1
return(k)
}
then this will work:
> source("abc.R")
> source("xyz.R")
> fooXYZ(3)
[1] 5
>
Even if there are cyclical dependencies, this wi...
Remove blank attributes from an Object in Javascript
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Hi, @EricNguyen, unlike C and other several languages, javascript does not have block scope for variables (only function scope), thus, the variable i will always leak into the scope after the for block.
– Gerardo Lima
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More lines in command window
Is there a possibility to get "more" lines into the command window (Console)?
3 Answers
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SET NAMES utf8 in MySQL?
...g by default from client connections (many are, depending on your location and platform.)
Read http://www.joelonsoftware.com/articles/Unicode.html in case you aren't aware how Unicode works.
Read Whether to use "SET NAMES" to see SET NAMES alternatives and what exactly is it about.
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How do I update my bare repo?
... doesn't show these updates in the bare repo. (Neither does git log --all, and neither does a working repo that created by cloning the bare repo - either via git log --all or by simply looking at new files that should show up there). It's a pretty quick test to see for yourself. Mostly I'm just curi...
Are multiple `.gitignore`s frowned on?
... file at the root of the repo than various ones throughout. Is there a standard best practice on this or some analysis online of when one approach is better than the other?
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How Many Seconds Between Two Dates?
So I have two dates YYYY-MM-DD and ZZZZ-NN-EE
9 Answers
9
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