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Is it possible only to declare a variable without assigning any value in Python?
Is it possible to declare a variable in Python, like so?:
14 Answers
14
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Python str vs unicode types
Working with Python 2.7, I'm wondering what real advantage there is in using the type unicode instead of str , as both of them seem to be able to hold Unicode strings. Is there any special reason apart from being able to set Unicode codes in unicode strings using the escape char \ ?:
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What is the size of column of int(11) in mysql in bytes?
What is the size of column of int(11) in mysql in bytes?
11 Answers
11
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What are the different usecases of PNG vs. GIF vs. JPEG vs. SVG?
...types of compression: Lossless and Lossy.
Lossless means that the image is made smaller, but at no detriment to the quality.
Lossy means the image is made (even) smaller, but at a detriment to the quality. If you saved an image in a Lossy format over and over, the image quality would get progres...
For-each over an array in JavaScript
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forEach accepts a callback function and, optionally, a value to use as this when calling that callback (not used above). The callback is called for each entry in the array, in order, skipping non-existent entries in sparse arrays. Although I only used one argument above, the callback is called wit...
Type List vs type ArrayList in Java [duplicate]
I understand that with (1), implementations of the List interface can be swapped. It seems that (1) is typically used in an application regardless of need (myself I always use this).
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Const before or const after?
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why is there two correct ways of specifying const data and in what situation would you prefer or need one over the other if any?
Essentially, the reason that the position of const within specifiers prior to an asterisk does not...
What's the point of OOP?
...rstand principles such as LSP); there seems to be little uniformity or consistency to the approaches that people take to modelling problem domains. All too often, the class is used simply for its syntactic sugar; it puts the functions for a record type into their own little namespace.
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What is java interface equivalent in Ruby?
...you have to be careful not to conflate the concept of the Interface, which is an abstract specification of the responsibilities, guarantees and protocols of a unit with the concept of the interface which is a keyword in the Java, C# and VB.NET programming languages. In Ruby, we use the former all th...
What is the fastest way to check if a class has a function defined?
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Yes, use getattr() to get the attribute, and callable() to verify it is a method:
invert_op = getattr(self, "invert_op", None)
if callable(invert_op):
invert_op(self.path.parent_op)
Note that getattr() normally throws exception when the attribute doesn't exist. However, if you specify a...