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Zip lists in Python
...x. 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: n is the length of the shortest argument (input)
len(numbers) =...
Why declare a struct that only contains an array in C?
...
It allows you to pass the array to a function by value, or get it returned by value from a function.
Structs can be passed by value, unlike arrays which decay to a pointer in these contexts.
...
Import SQL file into mysql
I have a database called nitm . I haven't created any tables there. But I have a SQL file which contains all the necessary data for the database. The file is nitm.sql which is in C:\ drive . This file has size of about 103 MB. I am using wamp server.
...
rails - Devise - Handling - devise_error_messages
...hould help you get started. :)
Another update
The resource object is actually the model that is being used by devise (go figure).
resource.class #=> User
resource.errors.class #=> ActiveModel::Error
It also appears to be defined in a higher scope (probably coming from the contro...
Should IBOutlets be strong or weak under ARC?
...t practice from Apple is for IBOutlets to be strong unless weak is specifically needed to avoid a retain cycle. As Johannes mentioned above, this was commented on in the "Implementing UI Designs in Interface Builder" session from WWDC 2015 where an Apple Engineer said:
And the last option I want...
How to scroll to specific item using jQuery?
...
element.scrollIntoView() - that is all that is required. Animation is standardised. See developer.mozilla.org/en-US/docs/Web/API/Element/scrollIntoView
– WickyNilliams
Feb 26 '16 at 11:46
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What are type lambdas in Scala and what are their benefits?
...ction of Either[A, B]. The monad typeclass looks like this:
trait Monad[M[_]] {
def point[A](a: A): M[A]
def bind[A, B](m: M[A])(f: A => M[B]): M[B]
}
Now, Either is a type constructor of two arguments, but to implement Monad, you need to give it a type constructor of one argument. The sol...
Is there a standard sign function (signum, sgn) in C/C++?
...T val) {
return (T(0) < val) - (val < T(0));
}
Benefits:
Actually implements signum (-1, 0, or 1). Implementations here using copysign only return -1 or 1, which is not signum. Also, some implementations here are returning a float (or T) rather than an int, which seems wasteful.
Works ...
Reflection - get attribute name and value on property
I have a class, lets call it Book with a property called Name. With that property, I have an attribute associated with it.
...
What happens to a detached thread when main() exits?
..._local) variables of other threads nor static objects.
This appears to be allowed to allow thread managers as static objects (note in [basic.start.term]/4 says as much, thanks to @dyp for the pointer).
Problems arise when the destruction of static objects has finished, because then execution enter...