total rewrite to interface handling; not complete but it compiles

generate/testdata/QueryWithDoubleAlias.graphql.go

@@ -1,6 +1,31 @@
-type Response struct {
-	User *struct {
-		ID     string
-		AlsoID string
-	} `json:"user"`
-}
+package test
+
+// Code generated by github.com/Khan/genql, DO NOT EDIT.
+
+import (
+	"context"
+
+	"github.com/Khan/genql/graphql"
+)
+
+type QueryWithDoubleAliasResponse struct {
+	User *User `json:"user"`
+}
+
+type User struct {
+	ID     string
+	AlsoID string
+}
+
+func QueryWithDoubleAlias(client *graphql.Client) (*QueryWithDoubleAliasResponse, error) {
+	var retval QueryWithDoubleAliasResponse
+	err := client.MakeRequest(context.Background(), `
+query QueryWithDoubleAlias {
+	user {
+		ID: id
+		AlsoID: id
+	}
+}
+`, &retval, nil)
+	return &retval, err
+}