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What is the difference between a pseudo-class and a pseudo-element in CSS?
...nsists of a "colon" (:) followed by the name of the pseudo-class and optionally by a value between parentheses.
Pseudo-classes are allowed in all sequences of simple selectors contained in a selector. Pseudo-classes are allowed anywhere in sequences of simple selectors, after the leading type s...
Removing “NUL” characters
...ty102.blogspot.ru/2010/04/findreplace-of-nul-objects-in-notepad.html
Basically you need to replace \x00 characters with regular expressions
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Omit rows containing specific column of NA
...# 2 2 10 33
EDIT: Only return rows with no NAs
If you want to eliminate all rows with at least one NA in any column, just use the complete.cases function straight up:
DF[complete.cases(DF), ]
# x y z
# 2 2 10 33
Or if completeFun is already ingrained in your workflow ;)
completeFun(DF, na...
GetHashCode Guidelines in C#
...ot GetHashCode right at every implementation. Second, value types are generally immutable with every value being a new instance rather than a modification of an existing instance.
– Jeff Yates
Jan 20 '09 at 18:46
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What is the difference between a URI, a URL and a URN?
...tion"). The term "Uniform Resource Name"
(URN) has been used historically to refer to both URIs under the
"urn" scheme [RFC2141], which are required to remain globally unique
and persistent even when the resource ceases to exist or becomes
unavailable, and to any other URI with ...
What's the difference between a proxy server and a reverse proxy server? [closed]
...ccurate, but perhaps too terse.
I will try to add some examples.
First of all, the word "proxy" describes someone or something acting on behalf of someone else.
In the computer realm, we are talking about one server acting on the behalf of another computer.
For the purposes of accessibility, I wi...
How to wait in bash for several subprocesses to finish and return exit code !=0 when any subprocess
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wait also (optionally) takes the PID of the process to wait for, and with $! you get the PID of the last command launched in background.
Modify the loop to store the PID of each spawned sub-process into an array, and then loop again waiting o...
How do I wrap text in a pre tag?
...
white-space:pre-line; (and all browser compatible flavors) seems more adequate in some cases (without tabs for instance) as it takes away the space at the beginning of the line (if there are some)
– MediaVince
Nov...
What is the difference between a JavaBean and a POJO?
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Note that a JavaBean can be and usually is a POJO and many POJOs are actually JavaBeans.
– Joachim Sauer
Sep 8 '09 at 14:21
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If REST applications are supposed to be stateless, how do you manage sessions?
...ined to be Representational State Transfer . I therefore don't understand all this stateless gobbledeygook that everyone keeps spewing.
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