Rust Trait Study

trait BitSet {
  	fn clear(&mut self, index: usize);
  	fn is_set(&self, index: usize) -> bool;
  	fn set(&mut self, index: usize);
  
  	fn toggle(&mut self, index: usize) {
    		if self.is_set(index) {
        		self.clear(index);  
      	} else {
        		self.set(index);  
      	}
  	}
}

impl BitSet for u64 {
  	fn clear(&mut self, index: usize) {
   			*self &= !(1 << index);
  	}
  
  	fn is_set(&self, index: usize) -> bool {
    		(*self >> index) & 1 == 1
  	}
  
  	fn set(&mut self, index: usize) {
    		 *self |= 1 << index; 
  	}
  
  	fn toggle(&mut self, index: usize) {
    		*self ^= 1 << index  
  	}
}