fn normalise(&mut self) {
        while !self.is_normalised() {
            self.blocks.pop();
        }
    }
// remove trailing zeroes that can affect equality comparison
// must be called after all shrinking operations
remove trailing zeroes that can affect equality comparison
must be called after all shrinking operations
remove trailing zeroes that can affect equality comparison must be called after all shrinking operations
fn normalise(&mut self) {
        while !self.is_normalised() {
            self.blocks.pop();
        }
    }
fn normalise ( & mut self ) { while ! self . is_normalised ( ) { self . blocks . pop ( ) ; } }
remove trailing zeroes that can affect equality comparison
must be called after all shrinking operations
remove trailing zeroes that can affect equality comparison must be called after all shrinking operations
&mut self
&mut self