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Constructor overload in TypeScript
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TypeScript allows you to declare overloads but you can only have one implementation and that implementation must have a signature that is compatible with all overloads. In your example, this can easily be done with an optional parameter...
Objective-C ARC: strong vs retain and weak vs assign
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@Pascal: weak references aren't allowed in deployment targets where the os is not 5.0 or higher. So for older projects you can still use assign, but if you move to newer versions you have to switch to weak
– Mattia
Feb...
Python __str__ versus __unicode__
...onfusing, but in 2.x we're stuck with them for compatibility reasons. Generally, you should put all your string formatting in __unicode__(), and create a stub __str__() method:
def __str__(self):
return unicode(self).encode('utf-8')
In 3.0, str contains characters, so the same methods are nam...
How do I correctly clean up a Python object?
...it close() statement is that you have to worry about people forgetting to call it at all or forgetting to place it in a finally block to prevent a resource leak when an exception occurs.
To use the with statement, create a class with the following methods:
def __enter__(self)
def __exit__(self...
Python's equivalent of && (logical-and) in an if-statement
... different name in Python.
The logical operators && and || are actually called and and or.
Likewise the logical negation operator ! is called not.
So you could just write:
if len(a) % 2 == 0 and len(b) % 2 == 0:
or even:
if not (len(a) % 2 or len(b) % 2):
Some additional information (...
In jQuery, how do I get the value of a radio button when they all have the same name?
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@PavanAlapati We cannot really tell you why without seeing your HTML as well; ideally, you would post a new question with your exact HTML snippet and the code you are using. You should only get undefined though, if: The name in the selector does not m...
How to add property to a class dynamically?
...ing on. Better late than never.
You can add a property to a class dynamically. But that's the catch: you have to add it to the class.
>>> class Foo(object):
... pass
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>>> foo = Foo()
>>> foo.a = 3
>>> Foo.b = property(lambda self: self.a + 1)
>>&...
Is there a TRY CATCH command in Bash
... writing a shell script and need to check that a terminal app has been installed. I want to use a TRY/CATCH command to do this unless there is a neater way.
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Is there any way to kill a Thread?
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It is generally a bad pattern to kill a thread abruptly, in Python and in any language. Think of the following cases:
the thread is holding a critical resource that must be closed properly
the thread has created several other threads ...
What is the most effective way for float and double comparison?
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Be extremely careful using any of the other suggestions. It all depends on context.
I have spent a long time tracing a bugs in a system that presumed a==b if |a-b|<epsilon. The underlying problems were:
The implicit presumption in an algorithm that if a==b and b==c then a==c.
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