7.1 – Changes in the Language

• The vararg system changed from the pseudo-argument arg with a table with the extra arguments to the vararg expression. (See compile-time option LUA_COMPAT_VARARG in luaconf.h.)
• There was a subtle change in the scope of the implicit variables of the for statement and for the repeat statement.
• The long string/long comment syntax ([[*string*]]) does not allow nesting. You can use the new syntax ([=[*string*]=]) in these cases. (See compile-time option LUA_COMPAT_LSTR in luaconf.h.)