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What is the difference between ? and Object in Java generics?
...Eclipse seems to be giving me an option to choose between a type of Object and a type of '?'.
6 Answers
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Can dplyr package be used for conditional mutating?
... TRUE ~ NA_real_))
Added - arithmetic/na_if If the values are numeric and the conditions (except for the default value of NA at the end) are mutually exclusive, as is the case in the question, then we can use an arithmetic expression such that each term is multiplied by the desired result using...
How to style the parent element when hovering a child element?
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Well, this question is asked many times before, and the short typical answer is: It cannot be done by pure CSS. It's in the name: Cascading Style Sheets only supports styling in cascading direction, not up.
But in most circumstances where this effect is wished, like in th...
How can I reverse a list in Python?
...cing, such as range(1,4)[::-1], reversed() is easier to read, runs faster, and uses substantially less memory. "
– Jim Oldfield
Aug 20 '16 at 15:55
5
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Python str vs unicode types
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unicode is meant to handle text. Text is a sequence of code points which may be bigger than a single byte. Text can be encoded in a specific encoding to represent the text as raw bytes(e.g. utf-8, latin-1...).
Note that unicode is not encoded! T...
Can I add jars to maven 2 build classpath without installing them?
Maven2 is driving me crazy during the experimentation / quick and dirty mock-up phase of development.
24 Answers
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django - why is the request.POST object immutable?
...nts a full set of mutation methods including __setitem__, __delitem__, pop and clear. It implements immutability by checking a flag when you call one of the mutation methods. And when you call the copy method you get another QueryDict instance with the mutable flag turned on.
For performance improve...
Using the scrollwheel in GNU screen
...tach from your screen, then screen -d -r to reattach, then ls a few times, and try to scroll back. It works for me.
What is this magic? Well, let's consult the manual pages.
screen(1) says:
termcapinfo term terminal-tweaks [window-tweaks]
[..]
The first argument specifies which terminal(s)...
How to access cookies in AngularJS?
...e AngularJS way to access cookies? I've seen references to both a service and a module for cookies, but no examples.
9 A...
What's the difference between __PRETTY_FUNCTION__, __FUNCTION__, __func__?
... the difference between __PRETTY_FUNCTION__ , __FUNCTION__ , __func__ , and where are they documented? How do I decide which one to use?
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