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Aren't Python strings immutable? Then why does a + “ ” + b work?
...the variable a to point at a new string "Dog eats treats". You didn't actually mutate the string "Dog". Strings are immutable, variables can point at whatever they want.
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What is a higher kinded type in Scala?
...pply to value arguments to "construct" a value.
Value constructors are usually called "functions" or "methods". These "constructors" are also said to be "polymorphic" (because they can be used to construct "stuff" of varying "shape"), or "abstractions" (since they abstract over what varies between ...
Import existing source code to GitHub
...me.git
If your local GIT repo is already set up, skips steps 2 and 3
Locally, at the root directory of your source, git init
2a. If you initialize the repo with a .gitignore and a README.md you should do a git pull {url from step 1} to ensure you don't commit files to source that you want to ign...
What's the best way to inverse sort in scala?
...
Both sortWith and sortBy have a compact syntax:
case class Foo(time:Long, str:String)
val l = List(Foo(1, "hi"), Foo(2, "a"), Foo(3, "X"))
l.sortWith(_.time > _.time) // List(Foo(3,X), Foo(2,a), Foo(1,hi))
l.sortBy(- _.time) // List(Foo(3,X), Foo(2,a), Foo(1,hi))
l....
How do you read from stdin?
I'm trying to do some of the code golf challenges, but they all require the input to be taken from stdin . How do I get that in Python?
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Why does C++11 not support designated initializer lists as C99? [closed]
... named function arguments. But as of right now, name arguments don't officially exist. See N4172 Named arguments for a proposal of this. It would make code less error prone and easier to read.
– David Baird
Nov 29 '15 at 15:11
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How do I best silence a warning about unused variables?
I have a cross platform application and in a few of my functions not all the values passed to functions are utilised. Hence I get a warning from GCC telling me that there are unused variables.
...
C++ mark as deprecated
...erface that I want to deprecate with portable C++.
When I Googled for this all I got was a Microsoft specific solution; #pragma deprecated and __declspec(deprecated) .
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Why is the order in dictionaries and sets arbitrary?
...der:
>>> {'bar': None, 'foo': None}
{'foo': None, 'bar': None}
All slots except 3 and 4 are empty, looping over the table first lists slot 3, then slot 4, so 'foo' is listed before 'bar'.
bar and baz, however, have hash values that are exactly 8 apart and thus map to the exact same slot...
Is it possible to print a variable's type in standard C++?
... return r;
}
The Results
With this solution I can do this:
int& foo_lref();
int&& foo_rref();
int foo_value();
int
main()
{
int i = 0;
const int ci = 0;
std::cout << "decltype(i) is " << type_name<decltype(i)>() << '\n';
std::cout << ...