Expression parser configuration

Each public pattern language selects duplicate-axis and ignored-axis rules through one explicit configuration value.

structure TorchLean.Tensor.Internal.Syntax.ExpressionConfig : Type

Duplicate and underscore rules for one expression.

• allowUnderscore : Bool

  Whether the name _ is accepted, including repeated occurrences.

• allowDuplicates : Bool

  Whether named axes may repeat; an ellipsis must still occur at most once.

def TorchLean.Tensor.Internal.Syntax.ExpressionConfig.transformation : ExpressionConfig

Rules used by transformation patterns.

def TorchLean.Tensor.Internal.Syntax.ExpressionConfig.parseShape : ExpressionConfig

Accept _ in parse_shape and einsum output expressions; only parse_shape ignores it.

def TorchLean.Tensor.Internal.Syntax.ExpressionConfig.einsumInput : ExpressionConfig

Rules used by an einsum input expression.