splinosaurus 0.2.2

flexible spline and surface library
Documentation 
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use crate::types::Scalar;
use core::ops::RangeInclusive;

#[derive(Debug, Clone)]
pub struct StepIter<T> {
    step: T,
    position: T,
    remaining: usize,
}

impl<T: Scalar> StepIter<T> {
    pub fn new(step: T, range: RangeInclusive<T>) -> Self {
        Self {
            step,
            position: *range.start(),
            remaining: ((*range.end() - *range.start()) / step).cast() + 1,
        }
    }
}

impl<T: Scalar> Iterator for StepIter<T> {
    type Item = T;

    fn next(&mut self) -> Option<Self::Item> {
        let position = self.position;
        self.position += self.step;

        if self.remaining > 0 {
            self.remaining -= 1;
            Some(position)
        } else {
            None
        }
    }

    fn size_hint(&self) -> (usize, Option<usize>) {
        (self.remaining, Some(self.remaining))
    }
}

impl<T: Scalar> ExactSizeIterator for StepIter<T> {}

#[cfg(test)]
mod tests {
    use super::*;
    use alloc::vec;
    use alloc::vec::Vec;

    #[test]
    fn it_iters_smoothly() {
        let step = StepIter::new(0.5, 0.0..=1.0);
        assert_eq!(3, step.len());
        assert_eq!(vec![0.0, 0.5, 1.0], step.collect::<Vec<_>>())
    }
}