diff --git a/examples/tree_of_nodes.v b/examples/tree_of_nodes.v new file mode 100644 index 0000000000..546ed23051 --- /dev/null +++ b/examples/tree_of_nodes.v @@ -0,0 +1,27 @@ +type Tree = Leaf | Node + +struct Leaf {} + +struct Node { + value int + left Tree + right Tree +} + +// NB: a match expression, infers the type of its result +// from the type of the return value in the first branch, +// => it needs an explicit int(0) cast here: +fn size(tree Tree) int { + return match tree { + Leaf { int(0) } + Node { 1 + size(tree.left) + size(tree.right) } + } +} + +fn main() { + node1 := Node{30, Leaf{}, Leaf{}} + node2 := Node{20, Leaf{}, Leaf{}} + tree := Node{10, node1, node2} + println('tree structure:\n $tree') + println('tree size: ${size(tree)}') +}