Enum ShapeTuple 

pub enum ShapeTuple {
    Leaf(usize),
    Nested(Vec<ShapeTuple>),
}

Hierarchical shape tuple (plan #38). Borrowed from MAX’s layout/int_tuple.mojo: shapes nest, so a ((B, S), (H, D)) expression captures the “outer batch+seq, inner heads+head_dim” structure of a tiled layout. Useful for kernels that want to reason about block-tiled sweeps without re-deriving the implied stride math each time.

Stays alongside the existing flat crate::Shape (which is what every op carries today). New code that benefits from hierarchy uses ShapeTuple; we don’t migrate Shape because the entire codebase is built around it and the win is concentrated in advanced layout / fusion code.

Variants

Leaf(usize)

Single concrete dimension.

Nested(Vec<ShapeTuple>)

Ordered list of sub-tuples. Nesting is unbounded.

Implementations

impl ShapeTuple

pub fn leaf(n: usize) -> Self

One-dim leaf. ShapeTuple::leaf(8).

pub fn nested(parts: Vec<ShapeTuple>) -> Self

Wrapping constructor for nested layouts.

pub fn flat(dims: &[usize]) -> Self

Convenience: build a flat tuple from &[usize]. Each element becomes a Leaf. flat(&[2, 3, 4]) is equivalent to Nested(vec![Leaf(2), Leaf(3), Leaf(4)]).

pub fn is_leaf(&self) -> bool

pub fn rank(&self) -> usize

Top-level rank. Leaves are rank 1; nested tuples are the length of the outer list.

pub fn product(&self) -> usize

Total element count, traversing the entire hierarchy.

pub fn flatten(&self) -> Vec<usize>

Flatten into a row-major sequence of leaves. Useful when converting to the existing Shape type.

pub fn get(&self, path: &[usize]) -> Option<&ShapeTuple>

Walk a path of indices through the hierarchy. Returns the sub-tuple at path or None if the path goes out of bounds at any level.

[] returns Some(self); [0] returns the first child.

Trait Implementations

impl Clone for ShapeTuple

fn clone(&self) -> ShapeTuple

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ShapeTuple

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

Formats the value using the given formatter.

impl Eq for ShapeTuple

impl PartialEq for ShapeTuple

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl StructuralPartialEq for ShapeTuple