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Why do we need Abstract factory design pattern?
...tract Factory has been accepted as the solution.
To the best of my understanding, these questions represent real concerns or problems that people had, so that should get you started with some real-life examples:
Is there a pattern for initializing objects created via a DI container
Can't combine ...
How can I start PostgreSQL server on Mac OS X?
I had forgotten to run the initdb command.
33 Answers
33
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Hidden Features of C++? [closed]
... that it can be used as an lvalue:
(a == 0 ? a : b) = 1;
which is shorthand for
if (a == 0)
a = 1;
else
b = 1;
Use with caution :-)
share
edited Jan 7 '09 at 21:...
Create a .txt file if doesn't exist, and if it does append a new line
I would like to create a .txt file and write to it, and if the file already exists I just want to append some more lines:
1...
How to do what head, tail, more, less, sed do in Powershell? [closed]
On windows, using Powershell, what are the equivalent commands to linux's head , tail , more , less and sed ?
7 Answe...
javax vs java package
What's the rationale behind the javax package? What goes into java and what into javax?
7 Answers
...
When and why would you seal a class?
In C# and C++/CLI the keyword sealed (or NotInheritable in VB) is used to protect a class from any inheritance chance (the class will be non-inheritable). I know that one feature of object-oriented programming is inheritance and I feel that the use of sealed goes against this feature, it stop...
How to merge dictionaries of dictionaries?
...for key in b:
if key in a:
if isinstance(a[key], dict) and isinstance(b[key], dict):
merge(a[key], b[key], path + [str(key)])
elif a[key] == b[key]:
pass # same leaf value
else:
raise Exception('Conflict at %...
How do you know when to use fold-left and when to use fold-right?
I'm aware that fold-left produces left-leaning trees and fold-right produces right-leaning trees, but when I reach for a fold, I sometimes find myself getting bogged down in headache-inducing thought trying to determine which kind of fold is appropriate. I usually end up unwinding the entire proble...
What is the difference between JOIN and UNION?
What is the difference between JOIN and UNION ? Can I have an example?
15 Answers
1...