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How to tell if a string is not defined in a Bash shell script
... not set, you can use:
if [ -z "${VAR+xxx}" ]; then echo VAR is not set at all; fi
if [ -z "$VAR" ] && [ "${VAR+xxx}" = "xxx" ]; then echo VAR is set but empty; fi
You probably can combine the two tests on the second line into one with:
if [ -z "$VAR" -a "${VAR+xxx}" = "xxx" ]; then echo VA...
JavaScript REST client Library [closed]
Is there a JavaScript library which allow me to perform all the REST operation like ( GET , POST , PUT and DELETE over HTTP or HTTPS )?
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Storing C++ template function definitions in a .CPP file
...post the relevant parts in the answer itself? Why is such referencing even allowed on SO. I have no clue what to look for in this link as it has been heavily changed since.
– Ident
Aug 16 '15 at 21:57
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How to assign colors to categorical variables in ggplot2 that have stable mapping?
...maintain consistent color schemes across multiple data frames that are not all obtained by subsetting a single large data frame. Managing the factors levels in multiple data frames can become tedious if they are being pulled from separate files and not all factor levels appear in each file.
One way...
Remove all child elements of a DOM node in JavaScript
How would I go about removing all of the child elements of a DOM node in JavaScript?
32 Answers
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Which is preferred: Nullable.HasValue or Nullable != null?
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The compiler replaces null comparisons with a call to HasValue, so there is no real difference. Just do whichever is more readable/makes more sense to you and your colleagues.
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What's the deal with a leading underscore in PHP class methods?
... { to give it some extra weight.
I've never heard of developers prefacing all their methods with underscores, so I can't begin to explain what causes that.
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How do I check that multiple keys are in a dict in a single pass?
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Well, you could do this:
>>> if all (k in foo for k in ("foo","bar")):
... print "They're there!"
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They're there!
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Using Mockito's generic “any()” method
...e able to compile lambda expressions, but it improves type inferences generally.
Primitive types
This doesn't work with primitive types, unfortunately:
public interface IBar {
void doPrimitiveStuff(int i);
}
verify(bar).doPrimitiveStuff(any()); // Compiles but throws NullPointerException
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Python: reload component Y imported with 'from X import Y'?
... verse (import this from interactive prompt to see the Zen of Python); and all the reasons why namespaces are a honking great idea (immediate local visual clues that the name's being looked up, ease of mocking/injecting in tests, ability to reload, ability for a module to change flexibly by redefini...