pub trait SecureRandomGenerator: Send + Sync {
// Required method
fn fill_byte(&self, dest: &mut [u8]);
// Provided methods
fn next_u64(&self) -> u64 { ... }
fn next_u32(&self) -> u32 { ... }
fn next_i64(&self) -> i64 { ... }
fn next_i32(&self) -> i32 { ... }
}