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Regex not operator
...xt following (hence: lookahead) this doesn't (hence: negative) match this. But it doesn't actually consume the characters it matches (hence: zero-width).
There are actually 4 combinations of lookarounds with 2 axes:
lookbehind / lookahead : specifies if the characters before or after the point ar...
How to directly initialize a HashMap (in a literal way)?
...etonMap("key", "value").
For Java Version 9 or higher:
Yes, this is possible now. In Java 9 a couple of factory methods have been added that simplify the creation of maps :
// this works for up to 10 elements:
Map<String, String> test1 = Map.of(
"a", "b",
"c", "d"
);
// this works ...
Difference between a Structure and a Union
Is there any good example to give the difference between a struct and a union ?
Basically I know that struct uses all the memory of its member and union uses the largest members memory space. Is there any other OS level difference?
...
How to set TextView textStyle such as bold, italic
How to set TextView style (bold or italic) within Java and without using the XML layout?
27 Answers
...
What is the colon operator in Ruby?
When I say { :bla => 1, :bloop => 2 } , what exactly does the : do? I read somewhere about how it's similar to a string, but somehow a symbol.
...
Is std::vector so much slower than plain arrays?
...t it's the general wisdom that std::vector is "implemented as an array," blah blah blah. Today I went down and tested it, and it seems to be not so:
...
In Python, how do I index a list with another list?
...
vanvan
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JavaScript equivalent of jQuery's extend method
I have a function that takes a config object as an argument. Within the function, I also have default object. Each of those objects contains properties that essentially work as settings for the rest of the code within the function. In order to prevent having to specify all of the settings wit...
What's the fastest way to merge/join data.frames in R?
...uplicate keys. (continued after code)
DF1 = data.frame(a = c(1, 1, 2, 2), b = 1:4)
DF2 = data.frame(b = c(1, 2, 3, 3, 4), c = letters[1:5])
merge(DF1, DF2)
b a c
1 1 1 a
2 2 1 b
3 3 2 c
4 3 2 d
5 4 2 e
DF1$c = DF2$c[match(DF1$b, DF2$b)]
DF1$c
[1] a b c e
Levels: a b c d e
> DF1
...
How to override the copy/deepcopy operations for a Python object?
I understand the difference between copy vs. deepcopy in the copy module. I've used copy.copy and copy.deepcopy before successfully, but this is the first time I've actually gone about overloading the __copy__ and __deepcopy__ methods. I've already Googled around and looked through the ...