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When to use Amazon Cloudfront or S3
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Be aware that Cloudfront evicts content very quickly. Setting max-age to more than a day does not mean you content will not be evicted if it hasn't been touched for 61 minutes. Not much use for user specific content as that amounts to infrequent access.
– B...
How do I get the object if it exists, or None if it does not exist?
... python is to wrap it in a try catch:
try:
go = SomeModel.objects.get(foo='bar')
except SomeModel.DoesNotExist:
go = None
What I did do, is to subclass models.Manager, create a safe_get like the code above and use that manager for my models. That way you can write: SomeModel.objects.safe_...
传感器组件 · App Inventor 2 中文网
... 属性
事件
方法
NFC
属性
事件
方法
方向传感器
属性
事件
方法
计步器
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Why does an SSH remote command get fewer environment variables then when run manually? [closed]
...d
by isatty(3)), or one started with the -i option. PS1 is
set and $- includes i if bash is interactive, allowing a
shell script or a startup file to test this state.
The following paragraphs describe how bash executes its
startup files. If any of the file...
Scroll to the top of the page using JavaScript?
How do I scroll to the top of the page using a JavaScript? It is desirable even if the scrollbar instantly jumps to the top. I'm not looking for a smooth scrolling.
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How to add texture to fill colors in ggplot2
...of both. Firstly draw the vertical lines and then add the horizontal lines setting fill as fill='transparent' to ensure the vertical lines are not drawn over.
Until there is a pattern update I hope some of you find this useful.
EDIT 2:
Additionally diagonal patterns may also be added. I added an ...
Occurrences of substring in a string
Why is the following algorithm not halting for me?
(str is the string I am searching in, findStr is the string I am trying to find)
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Moment.js: Date between dates
I'm trying to detect with Moment.js if a given date is between two dates. Since version 2.0.0, Tim added isBefore() and isAfter() for date comparison.
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Real mouse position in canvas [duplicate]
...mouse over a HTML5 canvas, but the only way that it seems to work well is if the canvas is in the position 0,0 (upper left corner) if I change the canvas position, for some reason it doesn't draw like it should. Here is my code.
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How to call methods dynamically based on their name? [duplicate]
...call a method dynamically when its name is contained in a string variable? For example:
5 Answers
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