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How do you use “
I just finished reading about scoping in the R intro , and am very curious about the <<- assignment.
6 Answers
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How to tell which commit a tag points to in Git?
I have a bunch of unannotated tags in the repository and I want to work out which commit they point to. Is there a command that that will just list the tags and their commit SHAs? Checking out the tag and looking at the HEAD seems a bit too laborious to me.
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Getting number of elements in an iterator in Python
...s are in an iterator in Python, in general, without iterating through each and counting?
16 Answers
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Greenlet Vs. Threads
I am new to gevents and greenlets. I found some good documentation on how to work with them, but none gave me justification on how and when I should use greenlets!
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How to convert a String to its equivalent LINQ Expression Tree?
...o you mean by "writing a parser (using Expression under the hood)" Parsing and then generating an expression tree, or does System.Linq.Expressions have some parsing mechanism?
– AK_
Jul 1 '13 at 14:51
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Why doesn't c++ have &&= or ||= for booleans?
Is there a "very bad thing" that can happen &&= and ||= were used as syntactic sugar for bool foo = foo && bar and bool foo = foo || bar ?
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How to check iOS version?
...lable(iOS 9, *) {}
In Objective-C, you need to check the system version and perform a comparison.
[[NSProcessInfo processInfo] operatingSystemVersion] in iOS 8 and above.
As of Xcode 9:
if (@available(iOS 9, *)) {}
The full answer …
In Objective-C, and Swift in rare cases, it's better to...
What does character set and collation mean exactly?
I can read the MySQL documentation and it's pretty clear. But, how does one decide which character set to use? On what data does collation have an effect?
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Why use apparently meaningless do-while and if-else statements in macros?
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The do ... while and if ... else are there to make it so that a
semicolon after your macro always means the same thing. Let's say you
had something like your second macro.
#define BAR(X) f(x); g(x)
Now if you were to use BAR(X); in an if ...
nginx missing sites-available directory
I installed Nginx on Centos 6 and I am trying to set up virtual hosts. The problem I am having is that I can't seem to find the /etc/nginx/sites-available directory.
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