Syntax/implementation question

[Martin <eden_martin_fuhrspam@...>]

Hi all,

I'm experimenting with lua syntax and cannot understand why in
interpreter I'm getting such output

Lua 5.3.3  Copyright (C) 1994-2016 Lua.org, PUC-Rio
> print(1), print(2), print(3)
1
2
3
nil	nil

When running this code from standalone file output is

$ lua test_something.lua
lua: test_something.lua:1: syntax error near ','

which is what I awaiting.

Any hints?