Add Helper 'index': get elem of array with the index

helpers/helpers.go

@@ -3,6 +3,7 @@ package pgghelpers
 import (
 	"encoding/json"
 	"fmt"
+	"reflect"
 	"regexp"
 	"strings"
 	"text/template"
@@ -90,6 +91,16 @@ var ProtoHelpersFuncMap = template.FuncMap{
 	"trimstr": func(cutset, s string) string {
 		return strings.Trim(s, cutset)
 	},
+	"index": func(array interface{}, i int) interface{} {
+		slice := reflect.ValueOf(array)
+		if slice.Kind() != reflect.Slice {
+			panic("Error in index(): given a non-slice type")
+		}
+		if i < 0 || i >= slice.Len() {
+			panic("Error in index(): index out of bounds")
+		}
+		return slice.Index(i).Interface()
+	},
 	"snakeCase":               xstrings.ToSnakeCase,
 	"getProtoFile":            getProtoFile,
 	"getMessageType":          getMessageType,