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How to “perfectly” override a dict?
..._contains__
# free setdefault, __eq__, and so on
import pickle
# works too since we just use a normal dict
assert pickle.loads(pickle.dumps(s)) == s
I wouldn't subclass dict (or other builtins) directly. It often makes no sense, because what you actually want t...
Why can't strings be mutable in Java and .NET?
Why is it that they decided to make String immutable in Java and .NET (and some other languages)? Why didn't they make it mutable?
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Difference between local and global indexes in DynamoDB
I'm curious about these two secondary indexes and differences between them. It is hard to imagine how this looks like. And I think, this will help more people than just me.
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A dependent property in a ReferentialConstraint is mapped to a store-generated column
...t you defined a bad column relation between your tables? different columns and one was set as autonumeric.
It happened to me.
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Is there an opposite of include? for Ruby Arrays?
...name)
...
end
ActiveSupport adds the exclude? method to Array, Hash, and String. This is not pure Ruby, but is used by a LOT of rubyists.
Source: Active Support Core Extensions (Rails Guides)
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Determine if Python is running inside virtualenv
...nside a virtual environment, sys.prefix points to the virtual environment, and sys.base_prefix is the prefix of the system Python the virtualenv was created from.
The above always works for Python 3 stdlib venv and for recent virtualenv (since version 20). Older versions of virtualenv used sys.real_...
Absolute positioning ignoring padding of parent
... its parent? I want an inner div to stretch across the width of its parent and to be positioned at the bottom of that parent, basically a footer. But the child has to honor the padding of the parent and it's not doing that. The child is pressed right up against the edge of the parent.
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How to play with Control.Monad.Writer in haskell?
I'm new to functional programming and recently learning at Learn You a Haskell , but when I went through this chapter , I got stuck with the program below:
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“new” keyword in Scala
...fferent things
> println(new Foo)
test@5c79cc94
> println(Foo())
7
And, since you mentioned Java classes: yes -- Java classes rarely have
companion objects with an apply method, so you must use new and the actual
class's constructor.
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【转】用App Inventor 2实现电子围栏功能 - App应用开发 - 清泛IT社区，为创新赋能！
... map’s drawn view. The value is a list of lists containing the northwest and southeast coordinates of the current view in the form ((North West) (South East)).设置或获取地图的边界，值是一个包含了西北和东南坐标的嵌套列表，格式为((北西)(南东))CenterFromString地...