Trait std::iter::Step
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[src]
pub trait Step: PartialOrd<Self> { fn step(&self, by: &Self) -> Option<Self>; fn steps_between(start: &Self, end: &Self, by: &Self) -> Option<usize>; fn steps_between_by_one(start: &Self, end: &Self) -> Option<usize>; fn is_negative(&self) -> bool; fn replace_one(&mut self) -> Self; fn replace_zero(&mut self) -> Self; fn add_one(&self) -> Self; fn sub_one(&self) -> Self; }
Objects that can be stepped over in both directions.
The steps_between
function provides a way to efficiently compare
two Step
objects.
Required Methods
fn step(&self, by: &Self) -> Option<Self>
Steps self
if possible.
fn steps_between(start: &Self, end: &Self, by: &Self) -> Option<usize>
Returns the number of steps between two step objects. The count is
inclusive of start
and exclusive of end
.
Returns None
if it is not possible to calculate steps_between
without overflow.
fn steps_between_by_one(start: &Self, end: &Self) -> Option<usize>
Same as steps_between
, but with a by
of 1
fn is_negative(&self) -> bool
Tests whether this step is negative or not (going backwards)
fn replace_one(&mut self) -> Self
Replaces this step with 1
, returning itself
fn replace_zero(&mut self) -> Self
Replaces this step with 0
, returning itself
fn add_one(&self) -> Self
Adds one to this step, returning the result
fn sub_one(&self) -> Self
Subtracts one to this step, returning the result