Clarify post-algorithm inputs

Author: sttts

post/defaulter.go

@@ -18,7 +18,8 @@ import (
 	"github.com/go-openapi/validate"
 )
 
-// ApplyDefaults applies defaults to data.
+// ApplyDefaults applies defaults to the underlying data of the result. The data must be a JSON
+// struct as returned by json.Unmarshal.
 func ApplyDefaults(r *validate.Result) {
 	fieldSchemata := r.FieldSchemata()
 	for key, schemata := range fieldSchemata {

post/prune.go

@@ -18,7 +18,8 @@ import (
 	"github.com/go-openapi/validate"
 )
 
-// Prune recursively removes all non-specified fields from the data.
+// Prune recursively removes all non-specified fields from the underlying data of the result.
+// The data must be a JSON struct as returned by json.Unmarshal.
 func Prune(r *validate.Result) {
 	prune(r.Data(), r)
 }