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Suppressing “warning CS4014: Because this call is not awaited, execution of the current method conti
This is not a duplicate of "How to safely call an async method in C# without await" .
8 Answers
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Split comma-separated strings in a column into separate rows
...solution,
and two additional variants of Jaap's data.table methods.
Overall 8 different methods were benchmarked on 6 different sizes of data frames using the microbenchmark package (see code below).
The sample data given by the OP consists only of 20 rows. To create larger data frames, these 20...
How do I watch a file for changes?
... file you want to watch).
Otherwise, polling will probably be the only really platform-independent option.
Note: I haven't tried any of these solutions.
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How can I calculate the number of lines changed between two commits in git?
...e - that's a task for git log. Ron DeVera touches on this, but you can actually do a lot more than what he mentions. Since git log internally calls the diff machinery in order to print requested information, you can give it any of the diff stat options - not just --shortstat. What you likely want to...
How to get the primary IP address of the local machine on Linux and OS X? [closed]
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You can alias the command in your .bashrc to create your own command called myip for instance.
alias myip="ifconfig | sed -En 's/127.0.0.1//;s/.*inet (addr:)?(([0-9]*\.){3}[0-9]*).*/\2/p'"
A much simpler way is hostname -I (hostname -i for older versions of hostname but see comments). However...
Use C++ with Cocoa Instead of Objective-C?
... superset of C. In Objective-C++, you can make objc-style message passing calls (like [some-objc-object callMethod];) from within a C++ function. Conversely, you can call C++ functions from within ObjC code like:
@interface MyClass {
MyCPPClass *cppInstance;
}
@end
@implementation MyClass
- (i...
C++ valarray vs. vector
I like vectors a lot. They're nifty and fast. But I know this thing called a valarray exists. Why would I use a valarray instead of a vector? I know valarrays have some syntactic sugar, but other than that, when are they useful?
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What is your single most favorite command-line trick using Bash? [closed]
We all know how to use <ctrl>-R to reverse search through history, but did you know you can use <ctrl>-S to forward search if you set stty stop "" ? Also, have you ever tried running bind -p to see all of your keyboard shortcuts listed? There are over 455 on Mac OS X by default. ...
SQL JOIN vs IN performance?
...here using a JOIN or an IN will give me the correct results... Which typically has better performance and why? How much does it depend on what database server you are running? (FYI I am using MSSQL)
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How do you make a web application in Clojure? [closed]
... is Compojure: http://github.com/weavejester/compojure/tree/master
It's small but powerful, and has beautifully elegant syntax. (It uses Jetty under the hood, but it hides the Servlet API from you unless you want it, which won't be often). Go look at the README at that URL, then download a snapshot...