Re: How to construct a tree data structure with differently static nodes types
On Monday, 23 November 2020 at 01:24:54 UTC, Max Haughton wrote: If you want to keep things simple, use OOP (classes). If you need to use structs, the "sumtype" may be just what you need (it's a bit more lightweight than std.algebraic in the standard library). If you want to implement this yourself then you need to write something called a tagged union. I'm looking for a data structure that is fully specified at compile time and statically dispatched rather than dynamically dispatched like OOP and so forth.
Re: How to construct a tree data structure with differently static nodes types
On Monday, 23 November 2020 at 01:20:04 UTC, data pulverizer
wrote:
Hi all,
I am trying to construct a tree data structure composed of
differently (statically) typed nodes. The basic case is a
binary tree. So you have a node like:
```
struct Node(T)
{
T value;
Node* next;
Node* prev;
}
void main()
{
auto x = Node!(int)(2);
auto y = Node!(double)(3.2);
x.next = &y; //gives error
}
```
Error: cannot implicitly convert expression & y of type
Node!double* to Node!int*
So implicity Node!(T) will produce an object with prev, and
next type Node!(T)*. But once I give them different types:
```
struct Node(T, P, N)
{
T value;
Node!(P...)* prev;
Node!(N...)* next;
}
```
I can no longer specify the types at all, they become
circularly referenced. Would appreciate the solution to this.
Many thanks.
p.s. Something equivalent can be built using tuples but it's less
convenient to write code for.
Re: How to construct a tree data structure with differently static nodes types
On Monday, 23 November 2020 at 01:20:04 UTC, data pulverizer
wrote:
Hi all,
I am trying to construct a tree data structure composed of
differently (statically) typed nodes. The basic case is a
binary tree. So you have a node like:
```
struct Node(T)
{
T value;
Node* next;
Node* prev;
}
void main()
{
auto x = Node!(int)(2);
auto y = Node!(double)(3.2);
x.next = &y; //gives error
}
```
Error: cannot implicitly convert expression & y of type
Node!double* to Node!int*
So implicity Node!(T) will produce an object with prev, and
next type Node!(T)*. But once I give them different types:
```
struct Node(T, P, N)
{
T value;
Node!(P...)* prev;
Node!(N...)* next;
}
```
I can no longer specify the types at all, they become
circularly referenced. Would appreciate the solution to this.
Many thanks.
If you want to keep things simple, use OOP (classes).
If you need to use structs, the "sumtype" may be just what you
need (it's a bit more lightweight than std.algebraic in the
standard library). If you want to implement this yourself then
you need to write something called a tagged union.
How to construct a tree data structure with differently static nodes types
Hi all,
I am trying to construct a tree data structure composed of
differently (statically) typed nodes. The basic case is a binary
tree. So you have a node like:
```
struct Node(T)
{
T value;
Node* next;
Node* prev;
}
void main()
{
auto x = Node!(int)(2);
auto y = Node!(double)(3.2);
x.next = &y; //gives error
}
```
Error: cannot implicitly convert expression & y of type
Node!double* to Node!int*
So implicity Node!(T) will produce an object with prev, and next
type Node!(T)*. But once I give them different types:
```
struct Node(T, P, N)
{
T value;
Node!(P...)* prev;
Node!(N...)* next;
}
```
I can no longer specify the types at all, they become circularly
referenced. Would appreciate the solution to this.
Many thanks.
