Add generic Map implementation (#108)

Instead of waiting for a good time to switch the `Map` implementation,
I've decided to just offer two implementations: one for Go versions
before 1.18, and one for 1.18 and onwards. This is achieved using build
tags in the source files.

This is obviously a breaking change for consumers of this library that
use Go 1.18 and onwards.

See #88

1 files changed, 13 insertions, 0 deletions

diff --git a/gomponents_non_generic.go b/gomponents_non_generic.go
new file mode 100644
index 0000000..56570d0
--- /dev/null
+++ b/gomponents_non_generic.go
@@ -0,0 +1,13 @@
+//go:build !go1.18
+// +build !go1.18
+
+package gomponents
+
+// Map something enumerable to a list of Nodes.
+func Map(length int, cb func(i int) Node) []Node {
+	var nodes []Node
+	for i := 0; i < length; i++ {
+		nodes = append(nodes, cb(i))
+	}
+	return nodes
+}