Initial commit

Proof-of-concept implementation. Bugs will occur.

vendor/github.com/goccy/go-yaml/parser/option.go

@@ -0,0 +1,12 @@
+package parser
+
+// Option represents parser's option.
+type Option func(p *parser)
+
+// AllowDuplicateMapKey allow the use of keys with the same name in the same map,
+// but by default, this is not permitted.
+func AllowDuplicateMapKey() Option {
+	return func(p *parser) {
+		p.allowDuplicateMapKey = true
+	}
+}