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Constructor in an Interface?
... but note that the use case @Sebi describes (calling overloaded methods from parent constructors) is a bad idea as explained in my answer.
– rsp
May 10 '10 at 15:57
44
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What are the benefits of functional programming? [closed]
...e the center of a loop, so this and other kinds of overhead are eliminated from your code.
The other major benefit is concurrency, which is easier to do with functional programming because the compiler is taking care of most of the operations which used to require manually setting up state variable...
Building executable jar with maven?
...the assembly generated by assembly:assembly and should contain the classes from the current module and its dependencies (if you used the descriptor jar-with-dependencies).
I get an error when I double-click on the first jar:
Could not find the main class: com.gorkwobble.logmanager.LogManager. Progr...
Using a strategy pattern and a command pattern
...sign patterns encapsulate an algorithm and decouple implementation details from their calling classes. The only difference I can discern is that the Strategy pattern takes in parameters for execution, while the Command pattern doesn't.
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python: How do I know what type of exception occurred?
...er way, like:
Present exceptions as dialogs in a GUI
Transfer exceptions from a worker thread or process to the controlling thread or process in a multithreading or multiprocessing application
So how to catch the generic exception? There are several ways. If you just want the exception object, d...
How do I get a Cron like scheduler in Python? [closed]
...fy your crontab. For example, suppose we define an Event class as below:
from datetime import datetime, timedelta
import time
# Some utility classes / functions first
class AllMatch(set):
"""Universal set - match everything"""
def __contains__(self, item): return True
allMatch = AllMatch...
SQLAlchemy default DateTime
... key should be an input to the Column function. Try this:
import datetime
from sqlalchemy import Column, Integer, DateTime
from sqlalchemy.ext.declarative import declarative_base
Base = declarative_base()
class Test(Base):
__tablename__ = 'test'
id = Column(Integer, primary_key=True)
...
“Private” (implementation) class in Python
...
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This is the official Python convention for 'internal' symbols; "from module import *" does not import underscore-prefixed objects.
Edit: Reference to the single underscore convention
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Printing without newline (print 'a',) prints a space, how to remove?
...llows you to set an end parameter. You can use it in >=2.6 by importing from __future__. I'd avoid this in any serious 2.x code though, as it will be a little confusing for those who have never used 3.x. However, it should give you a taste of some of the goodness 3.x brings.
>>> from __...
Introducing FOREIGN KEY constraint may cause cycles or multiple cascade paths - why?
...onship with cascading delete enabled by default again it will then cascade from Card to Side
So, you have two cascading delete paths from Stage to Side - which causes the exception.
You must either make the Stage optional in at least one of the entities (i.e. remove the [Required] attribute from ...