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What is the difference between old style and new style classes in Python?
What is the difference between old style and new style classes in Python? When should I use one or the other?
8 Answers
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C-like structures in Python
...thon 2.6. It's also possible to use Raymond Hettinger's named tuple recipe if you need to support Python 2.4.
It's nice for your basic example, but also covers a bunch of edge cases you might run into later as well. Your fragment above would be written as:
from collections import namedtuple
MyStru...
Java Generics (Wildcards)
...ces a restriction on the type by saying that it either has to extend a specific type (<? extends T> is known as an upper bound), or has to be an ancestor of a specific type (<? super T> is known as a lower bound).
The Java Tutorials have some pretty good explanations of generics in the ...
Single Line Nested For Loops
...a for loop.
Look at this longer list comprehension from the tutorial (the if part filters the comprehension, only parts that pass the if statement are passed into the final part of the list comprehension (here (x,y)):
>>> [(x, y) for x in [1,2,3] for y in [3,1,4] if x != y]
[(1, 3), (1, 4...
Print array elements on separate lines in Bash?
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Try doing this :
$ printf '%s\n' "${my_array[@]}"
The difference between $@ and $*:
Unquoted, the results are unspecified. In Bash, both expand to separate args
and then wordsplit and globbed.
Quoted, "$@" expands each element as a separate argument, while "$*"
expands to the a...
Formatting floats without trailing zeros
...ip('0').rstrip('.') -- guarantees fixed-point formatting rather than scientific notation, etc etc. Yeah, not as slick and elegant as %g, but, it works (and I don't know how to force %g to never use scientific notation;-).
s...
Using the HTML5 “required” attribute for a group of checkboxes?
...-of-the-box way to do that.
However, using jQuery, you can easily control if a checkbox group has at least one checked element.
Consider the following DOM snippet:
<div class="checkbox-group required">
<input type="checkbox" name="checkbox_name[]">
<input type="checkbox" na...
Python “extend” for a dictionary
...
keep in mind that update() directly modifies the dict and returns None.
– e18r
Dec 5 '15 at 23:15
6
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How does “304 Not Modified” work exactly?
My guess, if it's generated by the browser:
2 Answers
2
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Convert Array to Object
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Just want to point out - if you already have an array of sorted properties from the original object, using the spread operator is what will turn that array directly into a new object: { ...[sortedArray]}
– HappyHands31
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