Fixup reader interface

reader/reader.go

@@ -16,6 +16,7 @@ const (
 	TokenKey
 	TokenArray
 	TokenIndex
+	TokenValuePart
 	TokenValue
 	TokenEndNode
 	TokenEndArray
@@ -31,6 +32,8 @@ func TokenName(tok ReaderToken) string {
 		return "TokenArray"
 	case TokenIndex:
 		return "TokenIndex"
+	case TokenValuePart:
+		return "TokenValuePart"
 	case TokenValue:
 		return "TokenValue"
 	case TokenEndNode:
@@ -89,7 +92,7 @@ type NodeReader interface {
 	//    f({"items"},    TokenEndArray, nil)
 	//    f({},           TokenKey,      "count")
 	//    f({"count"},    TokenValue,    3)
-	//    f({},           TokenEndNode,   nil)
+	//    f({},           TokenEndNode,  nil)
 	//
 	// Iteration order for maps is fixed by the order of the pairs in memory.
 	//
@@ -104,5 +107,16 @@ type NodeReader interface {
 	// Returning any other error will abort the read process and the error will be
 	// passed as a return value of the Read() function.
 	//
+	// When the value to read is too large, the value can be transmitted in
+	// chunks. The chunks are all introduced by the TokenValuePart until the last
+	// chunk which is introduced by TokenValue
+	//
+	// Allowed value types are:
+	//
+	// - for numbers: int, int64, uint64, *"math/big".Int, float32, float64
+	// - for strings: string, []byte
+	// - for booleans: bool
+	// - for null: nil
+	//
 	Read(f ReadFun) error
 }