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I want to get the type of a variable at runtime
...stance, may want not to know what is the type of the variable, but to know if the type of the value is some specific type, such as this:
val x: Any = 5
def f[T](v: T) = v match {
case _: Int => "Int"
case _: String => "String"
case _ => "Unknown"
}
f(x)
Here it doesn't m...
What is Java String interning?
...gs will ensure that all strings having same contents share same memory. So if you have list of names where 'john' appears 1000 times, by interning you ensure only one 'john' is actually allocated memory.
This can be useful to reduce memory requirements of your program. But be aware that the cache i...
Loading basic HTML in Node.js
...
I just found one way using the fs library. I'm not certain if it's the cleanest though.
var http = require('http'),
fs = require('fs');
fs.readFile('./index.html', function (err, html) {
if (err) {
throw err;
}
http.createServer(function(request, re...
How to delete a file or folder?
..._path.mkdir()
file_path = directory_path / 'file'
file_path.touch()
and now:
>>> file_path.is_file()
True
Now let's delete them. First the file:
>>> file_path.unlink() # remove file
>>> file_path.is_file()
False
>>> file_path.exists()
False
We can use...
error C2664: “std::list::list(const std::allocator &)”: 不能将参数 1...
...转换为“const std::allocator &”错误日志：error C2664: std::list<_Ty>::list(const std::allocator<_Ty> &): 不能将参数 1 从std::vector<_Ty>转换为const std::...错误日志：
error C2664: “std::list<_Ty>::list(const std::allocator<_Ty> &)”: 不能将参数 1 从
“std::vect...
How to get all count of mongoose model?
How can I know the count of a model that data has been saved? there is a method of Model.count() , but it doesn't seem to work.
...
How to detect orientation change?
...on while using the camera with AVFoundation, and found that the didRotate (now deprecated) & willTransition methods were unreliable for my needs. Using the notification posted by David did work, but is not current for Swift 3.x/4.x.
Swift 4.2
The notification name has been changed.
The closure...
Is there any way to ignore INSTALL_FAILED_VERSION_DOWNGRADE on application install with the Android
...
And it seems to be documented now! Just not that you have to use -r -d, -rd will not work
– plaisthos
Jan 8 '16 at 12:44
...
How to remove illegal characters from path and filenames?
...blic string ReplaceInvalidChars(string filename)
{
return string.Join("_", filename.Split(Path.GetInvalidFileNameChars()));
}
This answer was on another thread by Ceres, I really like it neat and simple.
share
...
What is a word boundary in regex?
... \b\-?\d+\b ) but it appears that this does not work. I'd be grateful to know of ways of matching space-separated numbers.
...