Trait TrySparseIndex 

pub trait TrySparseIndex: Sized {
    type Error: Error;

    // Required methods
    fn index(&self) -> usize;
    fn try_from_index(index: usize) -> Result<Self, Self::Error>;

    // Provided methods
    fn from_index(index: usize) -> Self { ... }
    fn validate_sorted(
        indices: impl DoubleEndedIterator<Item = usize>,
    ) -> Result<(), Self::Error> { ... }
}

A trait for types that can be safely converted to and from indices.

This trait extends SparseIndex with fallible conversion methods, allowing for validation of index values during conversion. It’s particularly useful for bounded types like small integers or enums with gaps in their value range.

Examples

use omp_core::sparse_index::TrySparseIndex;

// u8 implements TrySparseIndex with bounds checking
assert!(u8::try_from_index(255).is_ok());
assert!(u8::try_from_index(256).is_err());

Required Associated Types

type Error: Error

The error type returned when index conversion fails.

Required Methods

fn index(&self) -> usize

Returns the index for this value.

fn try_from_index(index: usize) -> Result<Self, Self::Error>

Attempts to convert an index to this type.

Errors

Returns an error if the index is not valid for this type.

Provided Methods

fn from_index(index: usize) -> Self

Converts an index to this type, assuming the index is valid.

Safety

This method should only be called with indices that are known to be valid for the type. For fallible conversion, use Self::try_from_index.

fn validate_sorted( indices: impl DoubleEndedIterator<Item = usize>, ) -> Result<(), Self::Error>

Validates that every index in a sorted iterator is valid for this type.

The default checks each index individually: validity for an arbitrary type (e.g. an enum with gaps) is not an interval, so probing only the extremes is insufficient. Types whose valid indices form a contiguous range (like the integer implementations) override this with an O(1) min/max check.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementations on Foreign Types

impl TrySparseIndex for NonZero<i8>

type Error = NumericIndexError

fn index(&self) -> usize

fn from_index(index: usize) -> Self

fn try_from_index(index: usize) -> Result<Self, Self::Error>

fn validate_sorted( indices: impl DoubleEndedIterator<Item = usize>, ) -> Result<(), Self::Error>

impl TrySparseIndex for NonZero<i16>

type Error = NumericIndexError

fn index(&self) -> usize

fn from_index(index: usize) -> Self

fn try_from_index(index: usize) -> Result<Self, Self::Error>

fn validate_sorted( indices: impl DoubleEndedIterator<Item = usize>, ) -> Result<(), Self::Error>

impl TrySparseIndex for NonZero<i32>

type Error = NumericIndexError

fn index(&self) -> usize

fn from_index(index: usize) -> Self

fn try_from_index(index: usize) -> Result<Self, Self::Error>

fn validate_sorted( indices: impl DoubleEndedIterator<Item = usize>, ) -> Result<(), Self::Error>

impl TrySparseIndex for NonZero<i64>

type Error = NumericIndexError

fn index(&self) -> usize

fn from_index(index: usize) -> Self

fn try_from_index(index: usize) -> Result<Self, Self::Error>

fn validate_sorted( indices: impl DoubleEndedIterator<Item = usize>, ) -> Result<(), Self::Error>

impl TrySparseIndex for NonZero<isize>

type Error = NumericIndexError

fn index(&self) -> usize

fn from_index(index: usize) -> Self

fn try_from_index(index: usize) -> Result<Self, Self::Error>

fn validate_sorted( indices: impl DoubleEndedIterator<Item = usize>, ) -> Result<(), Self::Error>

impl TrySparseIndex for NonZero<u8>

type Error = NumericIndexError

fn index(&self) -> usize

fn from_index(index: usize) -> Self

fn try_from_index(index: usize) -> Result<Self, Self::Error>

fn validate_sorted( indices: impl DoubleEndedIterator<Item = usize>, ) -> Result<(), Self::Error>

impl TrySparseIndex for NonZero<u16>

type Error = NumericIndexError

fn index(&self) -> usize

fn from_index(index: usize) -> Self

fn try_from_index(index: usize) -> Result<Self, Self::Error>

fn validate_sorted( indices: impl DoubleEndedIterator<Item = usize>, ) -> Result<(), Self::Error>

impl TrySparseIndex for NonZero<u32>

type Error = NumericIndexError

fn index(&self) -> usize

fn from_index(index: usize) -> Self

fn try_from_index(index: usize) -> Result<Self, Self::Error>

fn validate_sorted( indices: impl DoubleEndedIterator<Item = usize>, ) -> Result<(), Self::Error>

impl TrySparseIndex for NonZero<u64>

type Error = NumericIndexError

fn index(&self) -> usize

fn from_index(index: usize) -> Self

fn try_from_index(index: usize) -> Result<Self, Self::Error>

fn validate_sorted( indices: impl DoubleEndedIterator<Item = usize>, ) -> Result<(), Self::Error>

impl TrySparseIndex for NonZero<usize>

type Error = NumericIndexError

fn index(&self) -> usize

fn from_index(index: usize) -> Self

fn try_from_index(index: usize) -> Result<Self, Self::Error>

fn validate_sorted( indices: impl DoubleEndedIterator<Item = usize>, ) -> Result<(), Self::Error>

impl TrySparseIndex for i8

type Error = NumericIndexError

fn index(&self) -> usize

fn from_index(index: usize) -> Self

fn try_from_index(index: usize) -> Result<Self, Self::Error>

fn validate_sorted( indices: impl DoubleEndedIterator<Item = usize>, ) -> Result<(), Self::Error>

impl TrySparseIndex for i16

type Error = NumericIndexError

fn index(&self) -> usize

fn from_index(index: usize) -> Self

fn try_from_index(index: usize) -> Result<Self, Self::Error>

fn validate_sorted( indices: impl DoubleEndedIterator<Item = usize>, ) -> Result<(), Self::Error>

impl TrySparseIndex for i32

type Error = NumericIndexError

fn index(&self) -> usize

fn from_index(index: usize) -> Self

fn try_from_index(index: usize) -> Result<Self, Self::Error>

fn validate_sorted( indices: impl DoubleEndedIterator<Item = usize>, ) -> Result<(), Self::Error>

impl TrySparseIndex for i64

type Error = NumericIndexError

fn index(&self) -> usize

fn from_index(index: usize) -> Self

fn try_from_index(index: usize) -> Result<Self, Self::Error>

fn validate_sorted( indices: impl DoubleEndedIterator<Item = usize>, ) -> Result<(), Self::Error>

impl TrySparseIndex for isize

type Error = NumericIndexError

fn index(&self) -> usize

fn from_index(index: usize) -> Self

fn try_from_index(index: usize) -> Result<Self, Self::Error>

fn validate_sorted( indices: impl DoubleEndedIterator<Item = usize>, ) -> Result<(), Self::Error>

impl TrySparseIndex for u8

type Error = NumericIndexError

fn index(&self) -> usize

fn from_index(index: usize) -> Self

fn try_from_index(index: usize) -> Result<Self, Self::Error>

fn validate_sorted( indices: impl DoubleEndedIterator<Item = usize>, ) -> Result<(), Self::Error>

impl TrySparseIndex for u16

type Error = NumericIndexError

fn index(&self) -> usize

fn from_index(index: usize) -> Self

fn try_from_index(index: usize) -> Result<Self, Self::Error>

fn validate_sorted( indices: impl DoubleEndedIterator<Item = usize>, ) -> Result<(), Self::Error>

impl TrySparseIndex for u32

type Error = NumericIndexError

fn index(&self) -> usize

fn from_index(index: usize) -> Self

fn try_from_index(index: usize) -> Result<Self, Self::Error>

fn validate_sorted( indices: impl DoubleEndedIterator<Item = usize>, ) -> Result<(), Self::Error>

impl TrySparseIndex for u64

type Error = NumericIndexError

fn index(&self) -> usize

fn from_index(index: usize) -> Self

fn try_from_index(index: usize) -> Result<Self, Self::Error>

fn validate_sorted( indices: impl DoubleEndedIterator<Item = usize>, ) -> Result<(), Self::Error>

impl TrySparseIndex for usize

type Error = NumericIndexError

fn index(&self) -> usize

fn from_index(index: usize) -> Self

fn try_from_index(index: usize) -> Result<Self, Self::Error>

fn validate_sorted( indices: impl DoubleEndedIterator<Item = usize>, ) -> Result<(), Self::Error>

Implementors

impl<T: SparseIndex> TrySparseIndex for T

Blanket implementation of TrySparseIndex for all SparseIndex types.

This allows any infallible sparse index type to be used in contexts requiring TrySparseIndex without additional boilerplate.

type Error = Infallible