logo
down
shadow

Moving and returning a mutable pointer


Moving and returning a mutable pointer

By : user197474
Date : November 22 2020, 10:48 AM
hop of those help? I am working through this Rust tutorial, and I'm trying to solve this problem: , There are a few mistakes in your code.
code :
fn main() {
    let mut p = vec![1i, 2i, 3i];
    increment_mut(p.as_mut_slice());

    for &x in p.iter() {
        print!("{} ", x);
    }
    println!("");
}

fn increment_mut(x: &mut [int]) {
    for i in x.iter_mut() {
        *i += 1;
    }
}


Share : facebook icon twitter icon
Returning mutable vs. returning immutable (non-member-)objects

Returning mutable vs. returning immutable (non-member-)objects


By : user3180353
Date : March 29 2020, 07:55 AM
around this issue I suppose the first variation was preferred because polymorphism was preferred.
In either case, both methods return an instance of NSMutableArray, the only difference being that the first one hides that fact from the caller. In other words, the first variation is not safer than the second. It's essentially using polymorphism to tell the caller that any type of NSArray might be returned. If you need that kind of flexibility in your code, it definitely has it's advantages. (e.g., if one day, for whatever reason, you need to return a custom NSArray subclass, your code won't break at that level).
code :
- (NSMutableArray *)mutableFooBar {
    NSMutableArray *fooArray = [NSMutableArray array];
    //populate fooArray
    return fooArray;
}
NSMutableArray *mutableArray = [NSMutableArray arrayWithArray:fooArray];
Moving a mutable trait object reference into a box

Moving a mutable trait object reference into a box


By : user3476639
Date : March 29 2020, 07:55 AM
Does that help
Shouldn't the mutability rules transitively ensure that the trait I get in accept_b is the sole owner of the underlying object and thereby support movement into a box?
How to get a mutable u32 pointer and cast it into an int pointer of C

How to get a mutable u32 pointer and cast it into an int pointer of C


By : Jagachandra
Date : March 29 2020, 07:55 AM
will help you Let's say I have a C function: , Finally I found the anwser, I have to give it a mutable sign:
code :
func(vec.as_ptr() as *mut c_char, &mut capacity as *mut c_uint)
Obj-C: using mutable and returning non mutable classes in methods

Obj-C: using mutable and returning non mutable classes in methods


By : croeer
Date : March 29 2020, 07:55 AM
I hope this helps you . It depends how much safety you require. If you return the object as an NSSet it will still be an NSMutableSet, so it could easily be cast back to one and modified.
Certainly, if you're creating a public API, I'd recommend returning a copy. For in internal project, perhaps the method signature already makes the intention clear enough.
F# Mutable list is returning an error stating it is not mutable

F# Mutable list is returning an error stating it is not mutable


By : Hasan Ileri
Date : September 27 2020, 02:00 AM
I hope this helps you . You have declared queue as mutable, but you are passing it as an argument that isn't mutable anymore. Since your queue variable is visible inside the push and pop you don't need to have it as parameters.
This should compile:
code :
  let create_job_list jobCount resultLis =
    let resultLis =
        [for i in 1..jobCount do yield System.Random().Next(10)]
    resultLis

  let job_list = create_job_list 10 []

  let mutable queue = []

  let push x=
      printfn "%A" x
      queue <- (x::queue)

  let pop resQueue =
      let resQ = resQueue |> List.rev
      match resQ with
      | head::tail -> printfn "%A" head; queue <- (tail |> List.rev)
      | [] -> failwith "No more jobs to do right now." 

  let rec jobQueue job_list =
      match job_list with
      | head::tail when head%2=1 -> (push head) |> ignore; jobQueue tail
      | head::tail when head%2=0 -> (pop) |> ignore; jobQueue tail
      | _ -> failwith "Empty list"
Related Posts Related Posts :
shadow
Privacy Policy - Terms - Contact Us © ourworld-yourmove.org