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Is it possible to make abstract classes in Python?
...g to instantiate the base class, so raise an exception. Here's a simple example:
class Base():
def __init__(self):
if type(self) is Base:
raise Exception('Base is an abstract class and cannot be instantiated directly')
# Any initialization code
print('In the...
How to permanently set $PATH on Linux/Unix? [closed]
...iate results,
Run (try as normal user and root):
source /etc/environment && export PATH
UPDATE:
If you use zsh (a.k.a Z Shell), add this line right after the comments in /etc/zsh/zshenv:
source /etc/environment
I encountered this little quirk on Ubuntu 15.10, but if your zsh is not ge...
How do lexical closures work?
...
Python is actually behaving as defined. Three separate functions are created, but they each have the closure of the environment they're defined in - in this case, the global environment (or the outer function's environment if the loop is ...
How to sum array of numbers in Ruby?
... You can use a similar trick with the map method: array.map(&:price).inject(:+)
– markquezada
Sep 8 '11 at 2:58
100
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How to run an EXE file in PowerShell with parameters with spaces and quotes
... evaluates the string, that is, it typically echos it to the screen, for example:
PS> "Hello World"
Hello World
If you want PowerShell to interpret the string as a command name then use the call operator (&) like so:
PS> & 'C:\Program Files\IIS\Microsoft Web Deploy\msdeploy.exe'
...
What is simplest way to read a file into String? [duplicate]
...ve one actual token, which is the entire file, so it can be read with one call to next().
There is a constructor that takes a File and a String charSetName (among many other overloads). These two constructor may throw FileNotFoundException, but like all Scanner methods, no IOException can be thrown...
How to get the root dir of the Symfony2 application?
...
Not the answer you're looking for? Browse other questions tagged php symfony symfony-2.8 symfony-config-component or ask your own question.
Breadth First Vs Depth First
...would visit the nodes in this order
A, B, D, C, E, F
Notice that you go all the way down one leg before moving on.
A breadth first traversal would visit the node in this order
A, B, C, D, E, F
Here we work all the way across each level before going down.
(Note that there is some ambiguity in...
Recent file history in Vim?
I would like to access recent files that I had opened and then closed in GVim. I open and close GVim frequently. I would like to access recent files from previous sessions as well.
...
Cloning a private Github repo
... errors when trying to clone repositories or download dependencies. (For example corporate firewalls are "notorious" for blocking git:.) If you run into this issue, you can force the use of https: instead, by running the following command: git config --global url."https://".insteadOf git://
...