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Use curly braces to initialize a Set in Python
...
There are two obvious issues with the set literal syntax:
my_set = {'foo', 'bar', 'baz'}
It's not available before Python 2.7
There's no way to express an empty set using that syntax (using {} creates an empty dict)
Those may or may not be important to you.
The section of the docs outlin...
Javascript shorthand ternary operator
...ng like that what you're looking for, where it defaults if undefined?
var foo = bar || 1; // 1
var bar = 2;
foo = bar || 1; // 2
By the way, this works for a lot of scenarios, including objects:
var foo = bar || {}; // secure an object is assigned when bar is absent
...
Easiest way to convert int to string in C++
...t i = 42;
std::string s = sstr( "i is: ", i );
puts( sstr( i ).c_str() );
Foo x( 42 );
throw std::runtime_error( sstr( "Foo is '", x, "', i is ", i ) );
Original answer:
Since "converting ... to string" is a recurring problem, I always define the SSTR() macro in a central header of my C++ sour...
How to exit git log or git diff [duplicate]
...nity wiki
4 revs, 2 users 71%Fred Foo
2
...
How to start an application without waiting in a batch file?
...a guess here, but your start invocation probably looks like this:
start "\Foo\Bar\Path with spaces in it\program.exe"
This will open a new console window, using “\Foo\Bar\Path with spaces in it\program.exe” as its title.
If you use start with something that is (or needs to be) surrounded by ...
Non greedy (reluctant) regex matching in sed?
...uence of digits) Live demo:
$ sed -r 's/([0-9]+).*|./\1/g' <<< 'foo 12 bar 34'
12
How does it work?
This regex benefits from an alternation |. At each position engine tries to pick the longest match (this is a POSIX standard which is followed by couple of other engines as well) which...
How to get the function name from within that function?
...
This might work for you:
function foo() { bar(); }
function bar() { console.log(bar.caller.name); }
running foo() will output "foo" or undefined if you call from an anonymous function.
It works with constructors too, in which case it would output the name...
Writing Unicode text to a text file?
...onvert it to a unicode-encoded string object before writing it to a file:
foo = u'Δ, Й, ק, م, ๗, あ, 叶, 葉, and 말.'
f = open('test', 'w')
f.write(foo.encode('utf8'))
f.close()
When you read that file again, you'll get a unicode-encoded string that you can decode to a unicode objec...
Difference between this and self in self-type annotations?
...class A.
The first two variants
trait A { self: B => ... }
trait A { foo: B => ... }
introduce self (respectively, foo) as an alias for this in trait A. This is useful for accessing the this reference from an inner class. I.e. you could then use self instead of A.this when accessing the t...
What happens if I define a 0-size array in C/C++?
... int content[];
};
The idea is that you would then allocate it so:
void foo(size_t x) {
Array* array = malloc(sizeof(size_t) + x * sizeof(int));
array->size = x;
for (size_t i = 0; i != x; ++i) {
array->content[i] = 0;
}
}
You might also use it statically (gcc extension):
Ar...
