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Split data frame string column into multiple columns
... stringr::str_split_fixed
library(stringr)
str_split_fixed(before$type, "_and_", 2)
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Returning null as an int permitted with ternary operator but not if statement
...itional operator (as described in the Java Language Specification, 15.25), and moves happily on. This will generate a NullPointerException at run time, which you can confirm by trying it.
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Difference between single and double square brackets in Bash
...ix shell compliant condition tests.
Double [[]] are an extension to the standard [] and are supported by bash and other shells (e.g. zsh, ksh). They support extra operations (as well as the standard posix operations). For example: || instead of -o and regex matching with =~. A fuller list of differ...
In what areas might the use of F# be more appropriate than C#? [closed]
...ft's fully supported languages employing many ideas incubated in OCaml, ML and Haskell.
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What framework for MVVM should I use? [closed]
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It really depends on what you are trying to achieve, and how much infrastructure you want in place already, plus the ease with which you can find samples that help you out. I'm going to declare an interest here, because I've been actively involved in at least one MVVM framework...
Why should the Gradle Wrapper be committed to VCS?
...of the gradle wrapper is to be able, without having ever installed gradle, and without even knowing how it works, where to download it from, which version, to clone the project from the VCS, to execute the gradlew script it contains, and to build the project without any additional step.
If all you ...
How to work around the lack of transactions in MongoDB?
...rd I don't wish to follow because it seems that many things could go wrong and I can't test it in every aspect. I'm having a hard time refactoring my project to perform atomic operations. I don't know whether this comes from my limited viewpoint (I have only worked with SQL databases so far), or whe...
DDD - the rule that Entities can't access Repositories directly
...ggregate roots are entities. The reason for this is separation of concerns and good layering. This doesn't make sense on small projects, but if you're on a large team you want to say, "You access a product through the Product Repository. Product is an aggregate root for a collection of entities, inc...
Why isn't SQL ANSI-92 standard better adopted over ANSI-89?
...ave found that people are still writing their SQL queries in the ANSI-89 standard:
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Use C++ with Cocoa Instead of Objective-C?
I would like to write applications that use C++ and the Cocoa frameworks because Apple is not making Carbon 64-bit capable. C++ seems to be pretty vanilla in its implementation on Linux and Windows but on Mac OS X it seems like additional Apple specific pieces of code are required (like an Obj-C wra...