Struct `StateID`

struct StateID(_)

The identifier of a finite automaton state.

It is represented by a u32 even on 64-bit systems in order to conserve space. Namely, on all targets, this type guarantees that its value will fit in a u32, i32, usize and an isize. This means that on 16-bit targets, for example, this type's maximum value will never overflow an isize, which means it will never overflow a i16 even though its internal representation is still a u32.

Safety

While a StateID is meant to guarantee that its value fits into usize without using as much space as a usize on all targets, callers must not rely on this property for safety. Callers may choose to rely on this property for correctness however. For example, creating a StateID with an invalid value can be done in entirely safe code. This may in turn result in panics or silent logical errors.

Implementations

`impl StateID`

fn new(value: usize) -> Result<StateID, StateIDError>

Create a new value that is represented by a "small index."

If the given index exceeds the maximum allowed value, then this returns an error.

const fn new_unchecked(value: usize) -> StateID

Create a new value without checking whether the given argument exceeds the maximum.

Using this routine with an invalid value will result in unspecified behavior, but not undefined behavior. In particular, an invalid ID value is likely to cause panics or possibly even silent logical errors.

Callers must never rely on this type to be within a certain range for memory safety.

const fn from_u32_unchecked(index: u32) -> StateID

Create a new value from a u32 without checking whether the given value exceeds the maximum.

Callers must never rely on this type to be within a certain range for memory safety.

fn must(value: usize) -> StateID

Like new, but panics if the given value is not valid.

const fn as_usize(self: &Self) -> usize

Return the internal value as a usize. This is guaranteed to never overflow usize.

const fn as_u64(self: &Self) -> u64

Return the internal value as a u64. This is guaranteed to never overflow.

const fn as_u32(self: &Self) -> u32

Return the internal value as a u32. This is guaranteed to never overflow u32.

const fn as_i32(self: &Self) -> i32

Return the internal value as a i32. This is guaranteed to never overflow an i32.

fn one_more(self: &Self) -> usize

Returns one more than this value as a usize.

Since values represented by a "small index" have constraints on their maximum value, adding 1 to it will always fit in a usize, u32 and a i32.

fn from_ne_bytes(bytes: [u8; 4]) -> Result<StateID, StateIDError>

Decode this value from the bytes given using the native endian byte order for the current target.

If the decoded integer is not representable as a small index for the current target, then this returns an error.

fn from_ne_bytes_unchecked(bytes: [u8; 4]) -> StateID

Decode this value from the bytes given using the native endian byte order for the current target.

This is analogous to new_unchecked in that is does not check whether the decoded integer is representable as a small index.

fn to_ne_bytes(self: &Self) -> [u8; 4]

Return the underlying integer as raw bytes in native endian format.

`impl Clone for StateID`

fn clone(self: &Self) -> StateID

`impl Copy for StateID`

`impl Debug for StateID`

fn fmt(self: &Self, f: &mut Formatter<'_>) -> Result

`impl Default for StateID`

fn default() -> StateID

`impl Eq for StateID`

`impl Freeze for StateID`

`impl From for StateID`

fn from(value: u8) -> StateID

`impl Hash for StateID`

fn hash<__H: $crate::hash::Hasher>(self: &Self, state: &mut __H)

`impl Ord for StateID`

fn cmp(self: &Self, other: &StateID) -> Ordering

`impl PartialEq for StateID`

fn eq(self: &Self, other: &StateID) -> bool

`impl PartialOrd for StateID`

fn partial_cmp(self: &Self, other: &StateID) -> Option<Ordering>

`impl RefUnwindSafe for StateID`

`impl Send for StateID`

`impl StructuralPartialEq for StateID`

`impl Sync for StateID`

`impl TryFrom for StateID`

fn try_from(value: u16) -> Result<StateID, StateIDError>

`impl TryFrom for StateID`

fn try_from(value: u32) -> Result<StateID, StateIDError>

`impl TryFrom for StateID`

fn try_from(value: u64) -> Result<StateID, StateIDError>

`impl TryFrom for StateID`

fn try_from(value: usize) -> Result<StateID, StateIDError>

`impl Unpin for StateID`

`impl UnsafeUnpin for StateID`

`impl UnwindSafe for StateID`

`impl<T> Any for StateID`

fn type_id(self: &Self) -> TypeId

`impl<T> Borrow for StateID`

fn borrow(self: &Self) -> &T

`impl<T> BorrowMut for StateID`

fn borrow_mut(self: &mut Self) -> &mut T

`impl<T> CloneToUninit for StateID`

unsafe fn clone_to_uninit(self: &Self, dest: *mut u8)

`impl<T> From for StateID`

fn from(t: T) -> T: Returns the argument unchanged.

`impl<T> ToOwned for StateID`

fn to_owned(self: &Self) -> T
fn clone_into(self: &Self, target: &mut T)

`impl<T, U> Into for StateID`

fn into(self: Self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of [From]<T> for U chooses to do.

`impl<T, U> TryFrom for StateID`

fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>

`impl<T, U> TryInto for StateID`

fn try_into(self: Self) -> Result<U, <U as TryFrom<T>>::Error>