Struct SymbolicShape 

pub struct SymbolicShape { /* private fields */ }

A shape pattern that can contain fixed, symbolic, and dynamic dimensions.

Think of it as a “shape template” that can be resolved to a concrete Shape once all symbolic dimensions are bound.

Examples

// Define a shape pattern for transformer input
let pattern = SymbolicShape::from(vec![
    SymDim::symbolic("Batch"),
    SymDim::symbolic("SeqLen"),
    SymDim::fixed(768),
]);

// Resolve with concrete bindings
let mut env = ShapeEnv::new();
env.bind("Batch", 32);
env.bind("SeqLen", 128);
let concrete = pattern.resolve(&env)?; // Shape([32, 128, 768])

// Or validate a concrete tensor shape
let guard = ShapeGuard::new(pattern);
assert!(guard.validate_shape(&Shape::new(vec![32, 128, 768]), &env));

Implementations

impl SymbolicShape

pub fn new(dims: Vec<SymDim>) -> Self

Create a new symbolic shape from a vector of SymDim.

pub fn from_shape(shape: &Shape) -> Self

Create a fully-fixed symbolic shape from a concrete shape.

pub fn rank(&self) -> usize

Number of dimensions.

pub fn dims(&self) -> &[SymDim]

Get the dimension patterns.

pub fn is_concrete(&self) -> bool

Check if all dimensions are fixed (fully concrete).

pub fn has_symbolic(&self) -> bool

Check if any dimension is symbolic or dynamic.

pub fn symbolic_names(&self) -> Vec<&str>

Get all symbolic dimension names used in this shape.

pub fn resolve(&self, env: &ShapeEnv) -> Result<Shape>

Try to resolve this symbolic shape to a concrete Shape.

Returns an error if any symbolic dimension is not bound in the env, or if any dimension is Dynamic (cannot resolve without a value).

pub fn resolve_with_default(&self, env: &ShapeEnv, default: usize) -> Shape

Try to resolve, falling back to a default for unresolved dims. Dynamic/unbound symbolic dims use the provided default value.

pub fn matches(&self, shape: &Shape, env: &ShapeEnv) -> bool

Check if a concrete shape matches this pattern.

Returns true if the shapes have the same rank and each dimension matches (fixed dims must be equal, symbolic dims must match their binding if bound, dynamic dims match anything).

pub fn unify(&self, shape: &Shape, env: &mut ShapeEnv) -> bool

Unify this pattern with a concrete shape, binding symbolic dims.

Returns true if unification succeeded (all dims compatible and symbolic bindings are consistent). On success, newly discovered bindings are added to env.

pub fn broadcast(&self, other: &SymbolicShape) -> Option<SymbolicShape>

Compute the output shape of a broadcasting operation between two symbolic shapes. Returns None if shapes are incompatible.

Trait Implementations

impl Clone for SymbolicShape

fn clone(&self) -> SymbolicShape

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for SymbolicShape

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

Formats the value using the given formatter.

impl Display for SymbolicShape

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

Formats the value using the given formatter.

impl From<Shape> for SymbolicShape

fn from(shape: Shape) -> Self

Converts to this type from the input type.

impl From<Vec<SymDim>> for SymbolicShape

fn from(dims: Vec<SymDim>) -> Self

Converts to this type from the input type.

impl PartialEq for SymbolicShape

fn eq(&self, other: &SymbolicShape) -> 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 Eq for SymbolicShape

impl StructuralPartialEq for SymbolicShape