Anonymous user
Parametric polymorphism: Difference between revisions
→{{header|C sharp|C#}}: Edited code style and added modern version
({{omit from|VBA|the Variant type is available.}}) |
(→{{header|C sharp|C#}}: Edited code style and added modern version) |
||
Line 119:
=={{header|C sharp|C#}}==
<lang csharp>
class BinaryTree<T>
{
public BinaryTree<T> left;
public BinaryTree(T value)
{
this.value = value;
}
public BinaryTree<U> Map<U>(Func<T, U> f)
{
BinaryTree<U> tree = new BinaryTree<U>(f(this.value));
if (this.left != null)
{
tree.left = this.left.Map(f);
}
if (this.right != null)
{
}
return tree;
}
}</lang>
Creating a tree of integers and using Map to generate a tree of doubles with every node half the value of the first:
<lang csharp>
{
{
b.right =
BinaryTree<double> b2 = b.Map(x => x * 0.5);
}
}</lang>
A version using more modern language constructs:
<lang csharp>using System;
class BinaryTree<T>
{
public BinaryTree<T> Left { get; }
public BinaryTree<T> Right { get; }
public T Value { get; }
public BinaryTree(T value, BinaryTree<T> left = null, BinaryTree<T> right = null)
{
this.Value = value;
this.Left = left;
this.Right = right;
}
public BinaryTree<U> Map<U>(Func<T, U> f)
{
return new BinaryTree<U>(f(this.Value), this.Left?.Map(f), this.Right?.Map(f));
}
public override string ToString()
{
var sb = new System.Text.StringBuilder();
this.ToString(sb, 0);
return sb.ToString();
}
private void ToString(System.Text.StringBuilder sb, int depth)
{
sb.Append(new string('\t', depth));
sb.AppendLine(this.Value?.ToString());
this.Left?.ToString(sb, depth + 1);
this.Right?.ToString(sb, depth + 1);
}
}
static class Program
{
static void Main()
{
var b = new BinaryTree<int>(6, new BinaryTree<int>(5), new BinaryTree<int>(7));
BinaryTree<double> b2 = b.Map(x => x * 0.5);
Console.WriteLine(b);
Console.WriteLine(b2);
}
}
</lang>
{{out}}
<pre>6
5
7
3
2.5
3.5</pre>
=={{header|Ceylon}}==
| |||