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Zip lists in Python
..., 'a'), (2, 'b'), (3, 'c')]
Input
Zero or more iterables [1] (ex. list, string, tuple, dictionary)
Output (list)
1st tuple = (element_1 of numbers, element_1 of letters)
2nd tuple = (e_2 numbers, e_2 letters)
…
n-th tuple = (e_n numbers, e_n letters)
List of n tuples:...
What is the most elegant way to remove a path from the $PATH variable in Bash?
...ultiple elements: in the first case, it adds the current dir (as the empty string; a potential security hole), in the second case it adds ` ` as a path element.
– Fred Foo
Mar 13 '11 at 17:26
...
Can I call a base class's virtual function if I'm overriding it?
... base->gogo1(7);
base->gogo2(7);
base->gogo3(7);
std::string s;
std::cout << "press any key to exit" << std::endl;
std::cin >> s;
return 0;
}
output
Derived
Derived :: gogo (int)
Derived :: gogo1 (int)
Derived :: gogo2 (int)
Derived :: gogo3 (in...
Unique ways to use the Null Coalescing operator [closed]
...
Well, first of all, it's much easier to chain than the standard ternary:
string anybody = parm1 ?? localDefault ?? globalDefault;
vs.
string anyboby = (parm1 != null) ? parm1
: ((localDefault != null) ? localDefault
: globalDefault);
It also works well if null-...
Factory pattern in C#: How to ensure an object instance can only be created by a factory class?
...work, and make the constructor private?
public BusinessClass
{
public string MyProperty { get; private set; }
private BusinessClass()
{
}
private BusinessClass(string myProperty)
{
MyProperty = myProperty;
}
public static BusinessClass CreateObject(string ...
@selector() in Swift?
...ed in the ObjC runtime). In that case, you can construct a Selector from a string: e.g. Selector("dynamicMethod:") — though you lose the compiler's validity checking. When you do that, you need to follow ObjC naming rules, including colons (:) for each parameter.
Selector availability: The method ...
Why is require_once so bad to use?
...red. Every *_once call means checking that log. So there's definitely some extra work being done there but enough to detriment the speed of the whole app?
... I really doubt it... Not unless you're on really old hardware or doing it a lot.
If you are doing thousands of *_once, you could do the wo...
How to select rows that have current day's timestamp?
... @ypercube oh i missed that but i was wondering why is the value on extra Using where; Using index?
– John Woo
Feb 8 '13 at 12:35
1
...
How to change the output color of echo in Linux
...
It may be more convenient to insert tput's output directly into your echo strings using command substitution:
echo "$(tput setaf 1)Red text $(tput setab 7)and white background$(tput sgr 0)"
Example
The above command produces this on Ubuntu:
Foreground & background colour commands
tp...
How to iterate over arguments in a Bash script
... when there are no positional parameters whereas "$*" expands to the empty string -- and yes, there is a difference between no arguments and one empty argument. See ${1:+"$@"} in /bin/sh`.
– Jonathan Leffler
Dec 12 '14 at 22:12
...