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I want to get the type of a variable at runtime
...variable" is always present, and can be passed around as a type parameter. For example:
val x = 5
def f[T](v: T) = v
f(x) // T is Int, the type of x
But depending on what you want to do, that won't help you. For instance, may want not to know what is the type of the variable, but to know if the t...
error LNK2019: 无法解析的外部符号_socket，该符号在函数 中被引用 - C/C+...
error LNK2019: 无法解析的外部符号_socket，该符号在函数 中被引用1>NetClient.obj : error LNK2019: 无法解析的外部符号 _closesocket@4，该符号在函数 _main 中被引用1>NetClient.obj : error L...1>NetClient.obj : error LNK2019: 无法解析的外部符号 _closesocket@...
Application not picking up .css file (flask/python)
...
You need to have a 'static' folder setup (for css/js files) unless you specifically override it during Flask initialization. I am assuming you did not override it.
Your directory structure for css should be like:
/app
- app_runner.py
/services
- ap...
iOS 7 status bar back to iOS 6 default style in iPhone app?
...ammatically in the traditional manner, or UIKit will update the appearance for you based on some new properties of UIViewController. The latter option is on by default. Check your app’s plist value for “ViewController-Based Status Bar Appearance” to see which one you’re using. If you set thi...
Custom Adapter for List View
I want to create a custom adapter for my list view. Is there any article that can walk me through how to create one and also explain how it works?
...
Is the C# static constructor thread safe?
... constructors are guaranteed to be run only once per application domain, before any instances of a class are created or any static members are accessed. https://docs.microsoft.com/en-us/dotnet/csharp/programming-guide/classes-and-structs/static-constructors
The implementation shown is thread safe f...
What are the differences between numpy arrays and matrices? Which one should I use?
...ain advantage of numpy matrices is that they provide a convenient notation
for matrix multiplication: if a and b are matrices, then a*b is their matrix
product.
import numpy as np
a = np.mat('4 3; 2 1')
b = np.mat('1 2; 3 4')
print(a)
# [[4 3]
# [2 1]]
print(b)
# [[1 2]
# [3 4]]
print(a*b)
# [[1...
How to output a multiline string in Bash?
...
Here documents are often used for this purpose.
cat << EOF
usage: up [--level <n>| -n <levels>][--help][--version]
Report bugs to:
up home page:
EOF
They are supported in all Bourne-derived shells including all versions of Bash.
...
Can you find all classes in a package using reflection?
...the VM which classes it can provide, instead they are just handed requests for classes, and have to return a class or throw an exception.
However, if you write your own class loaders, or examine the classpaths and it's jars, it's possible to find this information. This will be via filesystem operat...
How to know if two arrays have the same values
I have these two arrays: one is filled with information from an ajax request and another stores the buttons the user clicks on. I use this code (I filled with sample numbers):
...