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Closing WebSocket correctly (HTML5, Javascript)
... the connection gracefully? Like, what happens if user refreshes the page, or just closes the browser?
5 Answers
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(Built-in) way in JavaScript to check if a string is a valid number
...able (including a string) is a number, check if it is not a number:
This works regardless of whether the variable content is a string or number.
isNaN(num) // returns true if the variable does NOT contain a valid number
Examples
isNaN(123) // false
isNaN('123') // false
is...
What's the difference between “Layers” and “Tiers”?
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Logical layers are merely a way of
organizing your code. Typical layers
include Presentation, Business and
Data – the same as the traditional
3-tier model. But when we’re talking
about layers, we’re only talking about
logical organization of co...
What exactly is Arel in Rails 3.0?
I understand that it is a replacement for ActiveRecord and that it uses objects instead of queries.
4 Answers
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How to initialize log4j properly?
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Log4j by default looks for a file called log4j.properties or log4j.xml on the classpath.
You can control which file it uses to initialize itself by setting system properties as described here (Look for the "Default Initialization Procedure" section...
How do I use the nohup command without getting nohup.out?
...to close input manually. While closing input has no effect on the creation or not of nohup.out, it avoids another problem: if a background process tries to read anything from standard input, it will pause, waiting for you to bring it back to the foreground and type something. So the extra-safe versi...
How to “test” NoneType in python?
... can I question a variable that is a NoneType? I need to use if method, for example
7 Answers
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Manually adding a Userscript to Google Chrome
Instead of "installing" User-Scripts I found many tutorials on the web to add it manually. All of them told me to do the same steps:
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What is the fastest integer division supporting division by zero no matter what the result is?
... the assembly:
.globl f
.type f, @function
f:
pushl %ebp
xorl %eax, %eax
movl %esp, %ebp
movl 12(%ebp), %edx
testl %edx, %edx
sete %al
addl %edx, %eax
movl 8(%ebp), %edx
movl %eax, %ecx
popl %ebp
movl %edx, %eax
sa...
Dynamically Changing log4j log level
What are the different approaches for changing the log4j log level dynamically, so that I will not have to redeploy the application. Will the changes be permanent in those cases?
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