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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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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...
How to deep copy a list?
...s not a deep copy. You don't make a deep copy using list() (Both list(...) and testList[:] are shallow copies).
You use copy.deepcopy(...) for deep copying a list.
deepcopy(x, memo=None, _nil=[])
Deep copy operation on arbitrary Python objects.
See the following snippet -
>>> a = ...
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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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...
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...
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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Should I use JSLint or JSHint JavaScript validation? [closed]
I am currently validating my JavaScript against JSLint and making progress on, it's assisting me to write better JavaScript - in particular in working with the Jquery library.
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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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Can I use __init__.py to define global variables?
...package. But I don't know how to do this. Suppose I have a few subpackages and each with several modules. How can I access that variable from these modules?
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