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My Understanding of HTTP Polling, Long Polling, HTTP Streaming and WebSockets
...e read many posts on SO and the web regarding the keywords in my question title and learned a lot from them. Some of the questions I read are related to specific implementation challenges while others focus on general concepts. I just want to make sure I understood all of the concepts and the reason...
How do I check if file exists in Makefile so I can delete it?
...
The second top answer mentions ifeq, however, it fails to mention that these must be on the same level as the name of the target, e.g., to download a file only if it doesn't currently exist, the following code could be used:
download:
ifeq (,$(wildcard ./glob.c))
cur...
How do I use shell variables in an awk script?
...best way, most portable)
Use the -v option: (P.S. use a space after -v or it will be less portable. E.g., awk -v var= not awk -vvar=)
variable="line one\nline two"
awk -v var="$variable" 'BEGIN {print var}'
line one
line two
This should be compatible with most awk, and the variable is available ...
How is null + true a string?
...
Bizarre as this may seem, it's simply following the rules from the C# language spec.
From section 7.3.4:
An operation of the form x op y, where op is an overloadable binary operator, x is an expression of type X, and y is an expression of type Y,...
How to identify unused css definitions
Are there any good approaches to help identify unused css definitions in a project? A bunch of css files were pulled in and now I'm trying to clean things up a bit.
...
uint8_t vs unsigned char
...
It documents your intent - you will be storing small numbers, rather than a character.
Also it looks nicer if you're using other typedefs such as uint16_t or int32_t.
...
JavaScript unit test tools for TDD
I've looked into and considered many JavaScript unit tests and testing tools, but have been unable to find a suitable option to remain fully TDD compliant. So, is there a JavaScript unit test tool that is fully TDD compliant?
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Relational table naming convention [closed]
...e of the wonderful things about Standards are:
they are all integrated with each other
they work together
they were written by minds greater than ours, so we do not have to
debate them.
The standard table name refers to each row in the table, which is used in the all verbiage, not the total con...
What are the best practices for catching and re-throwing exceptions?
...g picture", but you do want to log the failure as close to the point where it happened as possible. In this case, you may want to catch, log, and re-throw:
try {
$connect = new CONNECT($db, $user, $password, $driver, $host);
}
catch (Exception $e) {
logException($e); // does something
t...
What is the purpose of the “final” keyword in C++11 for functions?
...is the purpose of the final keyword in C++11 for functions? I understand it prevents function overriding by derived classes, but if this is the case, then isn't it enough to declare as non-virtual your final functions? Is there another thing I'm missing here?
...