我正在swift中阅读sqlite。我不清楚这些是什么意思？
var errMsg: UnsafeMutablePointer<UnsafeMutablePointer<Int8>>? = nil
internal let SQLITE_STATIC = unsafeBitCast(0, to:sqlite3_destructor_type.self)
internal let SQLITE_TRANSIENT = unsafeBitCast(-1, to:sqlite3_destructor_type.self)