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Usages of Null / Nothing / Unit in Scala
...urns (meaning it cannot complete normally by returning, it could throw an exception). Nothing is never instantiated and is there for the benefit of the type system (to quote James Iry: "The reason Scala has a bottom type is tied to its ability to express variance in type parameters."). From the arti...
Create Directory When Writing To File In Node.js
...ike so:
// Creates /tmp/a/apple, regardless of whether `/tmp` and /tmp/a exist.
fs.mkdir('/tmp/a/apple', { recursive: true }, (err) => {
if (err) throw err;
});
or with a promise:
fs.promises.mkdir('/tmp/a/apple', { recursive: true }).catch(console.error);
Node <= 10.11.0
You can solv...
How to extract custom header value in Web API message handler?
...esn't serve any value as it will never return null. If the header doesn't exist you will get an InvalidOperationException. You need to use TryGetHeaders if it's possible the header might not exist in the request and check for a false response OR try/catch around the GetValues call (not recommended)....
rsync error: failed to set times on “/foo/bar”: Operation not permitted
...
Funny thing is I'm syncing ext3 to ext3 both OSes are linux. I've never had to use this switch before. -O did the trick, but I wish I didn't have to use it.
– d-_-b
Dec 14 '10 at 8:48
...
Add Variables to Tuple
..., 4, 5, 6)
c = b[1:] # (2, 3, 4, 5, 6)
And, of course, build them from existing values:
name = "Joe"
age = 40
location = "New York"
joe = (name, age, location)
share
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improve this answer
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Applying a function to every row of a table using dplyr?
...swer to this problem becomes:
iris %>%
rowwise() %>%
mutate(Max.Len= max(Sepal.Length,Petal.Length))
Non rowwise alternative
Five years (!) later this answer still gets a lot of traffic. Since it was given, rowwise is increasingly not recommended, although lots of people seem to find...
Compare floats in php
...
BEWARE! Choosing a fixed epsilon is a bad way just because it looks small, this comparison will return true in alot of precision errors when the numbers are small. A correct way would be to check if the relative error is smaller than the epsilon....
Extract filename and extension in Bash
I want to get the filename (without extension) and the extension separately.
37 Answers
...
What exactly is LLVM?
...d as a compiler framework, where you provide the "front end" (parser and lexer) and the "back end" (code that converts LLVM's representation to actual machine code).
LLVM can also act as a JIT compiler - it has support for x86/x86_64 and PPC/PPC64 assembly generation with fast code optimizations ai...
UIImage: Resize, then Crop
...ways set to the full screen size of the device.
@implementation UIImage (Extras)
#pragma mark -
#pragma mark Scale and crop image
- (UIImage*)imageByScalingAndCroppingForSize:(CGSize)targetSize
{
UIImage *sourceImage = self;
UIImage *newImage = nil;
CGSize imageSize = sourceImage....