Questions tagged [tuple-packing]
7 questions
50
votes
4 answers
Tuple unpacking order changes values assigned
I think the two are identical.
nums = [1, 2, 0]
nums[nums[0]], nums[0] = nums[0], nums[nums[0]]
print nums # [2, 1, 0]
nums = [1, 2, 0]
nums[0], nums[nums[0]] = nums[nums[0]], nums[0]
print nums # [2, 2, 1]
But the results are…
henry
- 563
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- 11
22
votes
4 answers
Packing scala tuple to custom class object
I have a tuple
val tuple = ("Mike", 40)
and a case class
case class Person(name: String, age: Int)
How can I pack my tuple to object of Person class? Are there any ways except this:
new Person(tuple._1, tuple._2)
Maybe somesing like…
Pavel Varchenko
- 727
- 1
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- 21
7
votes
6 answers
scala coalesces multiple function call parameters into a Tuple -- can this be disabled?
This is a troublesome violation of type safety in my project, so I'm looking for a way to disable it. It seems that if a function takes an AnyRef (or a java.lang.Object), you can call the function with any combination of parameters, and Scala will…
Landon Kuhn
- 76,451
- 45
- 104
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5
votes
5 answers
Converting a list of lists to a tuple in Python
I have a list of lists (generated with a simple list comprehension):
>>> base_lists = [[a, b] for a in range(1, 3) for b in range(1, 6)]
>>> base_lists
[[1,1],[1,2],[1,3],[1,4],[1,5],[2,1],[2,2],[2,3],[2,4],[2,5]]
I want to turn this entire list…
Sean Vieira
- 155,703
- 32
- 311
- 293
4
votes
1 answer
How to initialize a tuple with a given class having no copy constructor
I have a requirement where tuple needs to be initialized as follows. How do I create a tuple containing class A's object?
#include
#include
using namespace std;
class A{
int a;
public:
A(const A&)=delete;
A(int a):…
AAA
- 348
- 1
- 4
- 19
0
votes
1 answer
C++, match custom placeholders with function arguments
I am trying to write the piece of code which will do the following: let's assume we have a call of custom bind function
auto bind_obj = bind(some_func, _1, "test")
and after we have
auto res = bind_obj(42)
where the function some_func:
int…
Peter Leontev
- 107
- 1
- 8
0
votes
1 answer
Saving the results of a tuple_cat
I have code that I have taken from another source. The rest of the code works great. I am trying to append to a tuple using the following code:
// Because std::make_tuple can't be passed
// to higher order functions.
constexpr struct MakeTuple
{
…
Ivan
- 7,448
- 14
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- 134