Struct koto_parser::ConstantIndex

pub struct ConstantIndex(pub u8, pub u8, pub u8);

A 24 bit index for constants

Values are stored as little-endian 24 bit values.

Q: Why not just use a u32? A: Minimizing the memory footprint for a complex script with lots of constants seems like a healthy idea. Having a dedicated u24 type also forces the validity of a value to be checked when its first created; after creation an in-range index is guaranteed. Q: What if we need more than 2^24 constants in a script? A: Let’s wait and see, ConstantIndex can be transitioned to a u32 (along with the corresponding constant loading ops) if it really turns out to be necessary.

Tuple Fields

0: u8

1: u8

2: u8

Implementations

impl ConstantIndex

pub fn bytes(&self) -> [u8; 3]

The raw bytes representing the constant index

Trait Implementations

impl Clone for ConstantIndex

fn clone(&self) -> ConstantIndex

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for ConstantIndex

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

Formats the value using the given formatter.

impl Display for ConstantIndex

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

Formats the value using the given formatter.

impl From<&'_ ConstantIndex> for usize

fn from(x: &ConstantIndex) -> Self

Performs the conversion.

impl From<[u8; 2]> for ConstantIndex

fn from(x: [u8; 2]) -> Self

Performs the conversion.

impl From<[u8; 3]> for ConstantIndex

fn from(x: [u8; 3]) -> Self

Performs the conversion.

impl From<ConstantIndex> for usize

fn from(x: ConstantIndex) -> Self

Performs the conversion.

impl From<u8> for ConstantIndex

fn from(x: u8) -> Self

Performs the conversion.

impl Hash for ConstantIndex

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

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H) where
    H: Hasher, 

Feeds a slice of this type into the given Hasher.

impl PartialEq<ConstantIndex> for ConstantIndex

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

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &ConstantIndex) -> bool

This method tests for !=.

impl PartialEq<ConstantIndex> for usize

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

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl TryFrom<usize> for ConstantIndex

type Error = ConstantIndexTryFromOutOfRange

The type returned in the event of a conversion error.

fn try_from(x: usize) -> Result<Self, Self::Error>

Performs the conversion.

impl Copy for ConstantIndex

impl Eq for ConstantIndex

impl StructuralPartialEq for ConstantIndex