/// Macro to perform tensor transformations using simple expressions
///
/// This macro is re-exported as `candle_einops::einops`; the runtime crate's
/// documentation contains a complete runnable example.
/// Evaluates an explicit-output Einstein summation equation.
///
/// Supports any positive number of operands with named axes and at most one
/// `..` per axis list. Repeated input labels extract diagonals before
/// contraction. Use this through `candle_einops::einsum`; generated code calls
/// a private runtime ABI, so `candle-einops-macros` and `candle-einops` must use
/// exactly the same version.