From 88d7dd6f71cee09784a284c6a7287fe5b03c5f7f Mon Sep 17 00:00:00 2001
From: Andrey Petrov <andrey.petrov@shazow.net>
Date: Thu, 30 May 2019 11:12:51 -0400
Subject: [PATCH] WIP: Messing around with a clean reflectPositionArgs impl

---
 jsonrpc2/params.go | 36 ++++++++++++++++++++++++++++++++++++
 1 file changed, 36 insertions(+)
 create mode 100644 jsonrpc2/params.go

diff --git a/jsonrpc2/params.go b/jsonrpc2/params.go
new file mode 100644
index 0000000..39d8e1a
--- /dev/null
+++ b/jsonrpc2/params.go
@@ -0,0 +1,36 @@
+package jsonrpc2
+
+import (
+	"encoding/json"
+	"errors"
+	"reflect"
+)
+
+// reflectPositionalArgs takes the params of a JSONRPC message, and asserts
+// each positional argument into the reflected value of its type. It only
+// supports positional arguments for params, and will give an error for other
+// kinds of params.
+func reflectPositionalArgs(msgParams json.RawMessage, types []reflect.Type) ([]reflect.Value, error) {
+	// TODO: Add error type
+	if len(msgParams) == 0 {
+		return nil, errors.New("no params given")
+	}
+
+	args := make([]interface{}, 0, len(types))
+	if err := json.Unmarshal(msgParams, &args); err != nil {
+		return nil, err
+	}
+	if len(args) > types {
+		return nil, errors.New("too many arguments")
+	}
+
+	values := make([]reflect.Value, 0, len(types))
+	for i, arg := range args {
+		if arg == nil {
+			return nil, errors.New("not enough arguments")
+		}
+		value := reflect.New(types[i])
+	}
+
+	return values, nil
+}