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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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Better explanation of when to use Imports/Depends
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"Imports" is safer than "Depends" (and also makes a package using it a 'better citizen' with respect to other packages that do use "Depends").
A "Depends" directive attempts to ensure that a function from another package is available by attaching the other pa...
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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What is “thread local storage” in Python, and why do I need it?
...on-local variables (because each function call gets its own set of locals, and threads are always separate function calls.) And even then, only the variables themselves (the names that refer to objects) are local to the function; objects themselves are always global, and anything can refer to them.
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How can I use Homebrew to install both Python 2 and 3 on Mac?
I need to be able to switch back and forth between Python 2 and 3. How do I do that using Homebrew as I don't want to mess with path and get into trouble.
Right now I have 2.7 installed through Homebrew.
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How to automatically add user account AND password with a Bash script?
I need to have the ability to create user accounts on my Linux (Fedora 10) and automatically assign a password via a bash script(or otherwise, if need be).
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What does it mean by select 1 from table?
... is pretty unremarkable on its own, so normally it will be used with WHERE and often EXISTS (as @gbn notes, this is not necessarily best practice, it is, however, common enough to be noted, even if it isn't really meaningful (that said, I will use it because others use it and it is "more obvious" im...
Where to use EJB 3.1 and CDI?
I am making a Java EE based product in which I'm using GlassFish 3 and EJB 3.1.
2 Answers
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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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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...