GObject.Int64
GObject.Int64 represents the gint64 type in the GObject type system. You can pass this class object to methods taking a GObject.Type.
A gint64 value is an integer numeric value between -9223372036854775808 and 9223372036854775807, that is, a signed 64 bit number.
Note that because JS represents numbers in the double-precision floating point format, which only has 52 significant bits, converting to and from gint64 may result in loss of precision.
Creating a new object with new GObject.Int64 returns a Number object with value 0.
Calling GObject.Int64(arg) will coerce the argument to a number.