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How to serve an image using nodejs
...
2016 Update
Examples with Express and without Express that actually work
This question is over 5 years old but every answer has some problems.
TL;DR
Scroll down for examples to serve an image with:
express.static
express
connect
http
net
All of the examples are also on GitHub: htt...
Creating a singleton in Python
...mple implementation:
class Singleton(type):
_instances = {}
def __call__(cls, *args, **kwargs):
if cls not in cls._instances:
cls._instances[cls] = super(Singleton, cls).__call__(*args, **kwargs)
return cls._instances[cls]
class Logger(object):
__meta...
Why do we need virtual functions in C++?
... a rat."
So far so good, right? Animals eat generic food, cats eat rats, all without virtual.
Let's change it a little now so that eat() is called via an intermediate function (a trivial function just for this example):
// This can go at the top of the main.cpp file
void func(Animal *xyz) { xyz-...
How does Django's Meta class work?
I am using Django which allows people to add extra parameters to a class by using class Meta .
6 Answers
...
Use of *args and **kwargs [duplicate]
...u're not sure how many arguments might be passed to your function, i.e. it allows you pass an arbitrary number of arguments to your function. For example:
>>> def print_everything(*args):
for count, thing in enumerate(args):
... print( '{0}. {1}'.format(count, thing))
...
...
“Private” (implementation) class in Python
I am coding a small Python module composed of two parts:
7 Answers
7
...
How to make an array of arrays in Java
Hypothetically, I have 5 string array objects:
4 Answers
4
...
Get file version in PowerShell
...
Since PowerShell can call .NET classes, you could do the following:
[System.Diagnostics.FileVersionInfo]::GetVersionInfo("somefilepath").FileVersion
Or as noted here on a list of files:
get-childitem * -include *.dll,*.exe | foreach-object { "...
Assigning a variable NaN in python without numpy
...aking) be said to be equal to one another -- see What is the rationale for all comparisons returning false for IEEE754 NaN values? for more details and information.
Instead, use math.isnan(...) if you need to determine if a value is NaN or not.
Furthermore, the exact semantics of the == operation...
How do I get Flask to run on port 80?
...roxy HTTP traffic through apache2 to Flask.
This way, apache2 can handle all your static files (which it's very good at - much better than the debug server built into Flask) and act as a reverse proxy for your dynamic content, passing those requests to Flask.
Here's a link to the official documen...