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How can I get nth element from a list?
...hat the standard library contains some such partial functions (head, last, etc.). For safety, use an option type Maybe, or the Safe module.
Example of a reasonably efficient, robust total (for indices ≥ 0) indexing function:
data Maybe a = Nothing | Just a
lookup :: Int -> [a] -> Maybe a
...
What is the difference between “def” and “val” to define a function
... x % 2 == 0)" function (not any other statement before i.e. println("val") etc. Invoking event2 with different parameters will actually invoke "(x => x % 2 == 0)" code, as only that is saved with event2.
scala> even2(2)
res7: Boolean = true
scala> even2(3)
res8: Boolean = false
Just to ...
Convert char to int in C and C++
... = a would suffice */
to convert the character '0' -> 0, '1' -> 1, etc, you can write
char a = '4';
int ia = a - '0';
/* check here if ia is bounded by 0 and 9 */
Explanation:
a - '0' is equivalent to ((int)a) - ((int)'0'), which means the ascii values of the characters are subtracted fro...
Vim: Creating parent directories on save
...nes the :W command. Ideally, I'd like to have all of :w!, :wq, :wq!, :wall etc work the same, but I'm not sure if it's possible without basically reimplementing them all with custom functions.
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How do I add more members to my ENUM-type column in MySQL?
...UM. ENUM is, at it's core, a mapping of 0 -> Option 1, 1-> Option 2, etc. Adding to that shouldn't cause an issue.
– JoshStrange
Feb 10 '15 at 20:07
2
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Create a menu Bar in WPF?
... comprehensive tutorial on WPF Menus, Command Binding adding Shortcut keys etc at youtu.be/bdmVWGjpA_8
– Zaheer
Apr 26 at 1:18
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How can I find WPF controls by name or type?
...urn null;
T foundChild = null;
int childrenCount = VisualTreeHelper.GetChildrenCount(parent);
for (int i = 0; i < childrenCount; i++)
{
var child = VisualTreeHelper.GetChild(parent, i);
// If the child is not of the request child type child
T childType = child as T;
if (...
Why is Swift compile time so slow?
... with high accuracy whether your refactorings (explicit casts, type hints, etc...) are lowering compile times for specific files or not.
NOTE: technically you could also do it with xcodebuild but the output is incredibly verbose and hard to consume.
...
Test for non-zero length string in Bash: [ -n “$var” ] or [ “$var” ]
...h a POSIX-compliant test implementation -- not just bash, but ash/dash/ksh/etc.
– Charles Duffy
Aug 15 '18 at 17:37
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Why does C++ not allow inherited friendship?
...ved types (nor should I. They may even be developed by different companies etc). Thus I would be unable to change Foo as doing so would introduce breaking changes into the code base (as I could not modify all class derived from Bar).
Thus if friendship was inherited you are inadvertently introducin...