rendarray 0.2.0-alpha.8

use std::fmt;
use std::error::Error;
use super::{
    Ix,
};

/// An error that can be produced by `.into_shape()`
#[derive(Clone, Debug)]
pub enum ShapeError {
    /// incompatible shapes in reshape, (from, to)
    IncompatibleShapes(Box<[Ix]>, Box<[Ix]>),
    /// incompatible layout: not contiguous
    IncompatibleLayout,
    /// Dimension too large (shape)
    DimensionTooLarge(Box<[Ix]>),
}

impl Error for ShapeError {
    fn description(&self) -> &str {
        match *self {
            ShapeError::IncompatibleShapes(..) =>
                "incompatible shapes in reshape",
            ShapeError::IncompatibleLayout =>
                "incompatible layout: not not contiguous",
            ShapeError::DimensionTooLarge(..) =>
                "dimension too large",
        }
    }
}

impl fmt::Display for ShapeError {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        match *self {
            ShapeError::IncompatibleShapes(ref a, ref b) => {
                write!(f, "incompatible shapes, attempted from: {:?}, to: {:?}",
                       a, b)
            }
            ShapeError::IncompatibleLayout => {
                write!(f, "{}", self.description())
            }
            ShapeError::DimensionTooLarge(ref a) => {
                write!(f, "dimension too large in shape {:?}", a)
            }
        }
    }
}