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What is Scala's yield?
...I use yield instead of map? This map code is equivalent val res = args.map(_.toUpperCase) , right?
– Geo
Jun 27 '09 at 12:23
4
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What's the best way to trim std::string?
I'm currently using the following code to right-trim all the std::strings in my programs:
46 Answers
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How to rename a single column in a data.frame?
...r.name'
This code pretty much does the following:
names(df) looks into all the names in the df
[names(df) == old.var.name] extracts the variable name you want to check
<- 'new.var.name' assigns the new variable name.
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Where is the Keytool application?
...achine, you would normally find the jdk at
C:\Program Files\Java\jdk1.8.0_121\bin
It is used for managing keys and certificates you can sign things with, in your case, probably a jar file.
If you provide more details of what you need to do, we could probably give you a more specific answer.
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Easiest way to convert int to string in C++
...icking up a discussion with @v.oddou a couple of years later, C++17 has finally delivered a way to do the originally macro-based type-agnostic solution (preserved below) without going through macro uglyness.
// variadic template
template < typename... Args >
std::string sstr( Args &&....
Reintegrate can only be used if revisions X through Y were previously merged from to reintegra
Been using SVN branches with Tortoise 1.6. I've been periodically merging the trunk into the branch to keep it up to date.
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How should one use std::optional?
...std::string s, int& i);
Another way that this could be done is especially bad:
int* try_parse_int(std::string s); //return nullptr if fail
This requires dynamic memory allocation, worrying about ownership, etc. - always prefer one of the other two signatures above.
Another example:
clas...
How to remove a TFS Workspace Mapping?
...stating "Show Remote Workspaces" - just tick that and you'll get a list of all your enlistments:
From the command line
Call "tf workspace" from a developer command prompt. It will bring up the "Manage Workspaces" directly!
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Can I load a UIImage from a URL?
...llpaper.net/iphone/img/app/i/p/iphone-4s-wallpapers-mobile-backgrounds-dark_2466f886de3472ef1fa968033f1da3e1_raw_1087fae1932cec8837695934b7eb1250_raw.jpg");
var err: NSError?
var imageData :NSData = NSData.dataWithContentsOfURL(url,options: NSDataReadingOptions.DataReadingMappedIfSafe, error...
Amazon Interview Question: Design an OO parking lot [closed]
...s.
ParkingSpace has an Entrance.
Entrance has a location or more specifically, distance from Entrance.
ParkingLotSign is a class.
ParkingLot has a ParkingLotSign.
ParkingLot has a finite number of ParkingSpaces.
HandicappedParkingSpace is a subclass of ParkingSpace.
RegularParkingSpace is a s...