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Best way to iterate through a Perl array
...ay elements occurs. ($_ is aliased to the element in #1, but #2 and #3 actually copy the scalars from the array.)
#5 might be similar.
In terms memory usage: They're all the same except for #5.
for (@a) is special-cased to avoid flattening the array. The loop iterates over the indexes of the array...
How to write a large buffer into a binary file in C++, fast?
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Try the following, in order:
Smaller buffer size. Writing ~2 MiB at a time might be a good start. On my last laptop, ~512 KiB was the sweet spot, but I haven't tested on my SSD yet.
Note: I've noticed that very large buffers tend to decrease performance. ...
jQuery scroll() detect when user stops scrolling
...vent handler function for one or more events to the selected elements and calls the handler function if the event was not triggered for a given interval. This is useful if you want to fire a callback only after a delay, like the resize event, or such.
It is important to check the github-repo for up...
Are lists thread-safe?
... data is not protected. For example:
L[0] += 1
is not guaranteed to actually increase L[0] by one if another thread does the same thing, because += is not an atomic operation. (Very, very few operations in Python are actually atomic, because most of them can cause arbitrary Python code to be call...
django admin - add custom form fields that are not part of the model
... ModelForm class and then declare your extra fields inside that as you normally would. I've also given an example of how you might use these values in form.save():
from django import forms
from yourapp.models import YourModel
class YourModelForm(forms.ModelForm):
extra_field = forms.CharFiel...
SQL to determine minimum sequential days of access?
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@Artem: That was what I initially thought but when I thought about it, if you have an index on (UserId, CreationDate), the records will show up consecutively in the index and it should perform well.
– Mehrdad Afshari
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Queue.Queue vs. collections.deque
...nd collections.deque serve different purposes. Queue.Queue is intended for allowing different threads to communicate using queued messages/data, whereas collections.deque is simply intended as a datastructure. That's why Queue.Queue has methods like put_nowait(), get_nowait(), and join(), whereas co...
Loop through an array of strings in Bash?
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Note that the double quotes around "${arr[@]}" are really important. Without them, the for loop will break up the array by substrings separated by any spaces within the strings instead of by whole string elements within the array. ie: if you had declare -a arr=("element 1" "ele...
Missing Push Notification Entitlement
...cation enabled)
App Store and Ad Hoc certificate
Apple Push Notification service SSL (Sandbox) certificate
Third Provisioning Profiles
From Distribution section create App Store profile with your id
Finally
while you upload your bin , you must check what provisioning profile used...
Conditional compilation and framework targets
... are a few minor places where code for my project may be able to be drastically improved if the target framework were a newer version. I'd like to be able to better leverage conditional compilation in C# to switch these as needed.
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