Compiled expression evaluation — Expression.compile() and
AffineExpression.compile() return a fast callable for fully-bound
MV/scalar bindings that equals __call__ but is reduced to the numeric
contraction; __call__/evaluate route the same case through the compiled
path automatically.
Multilinear AffineExpression.get_tensor() — a single variable appearing
k >= 1 times per term now extracts as a rank-(1 + k)MVTensor, so a
quadratic operator (Omega twice) can be precomputed once and contracted
with np.einsum("ijk,j,k->i", Q, c, c).
BladeMask.ids_outside(mv) — a cheap single-call membership diff of an
MV against a mask, used to validate expression bindings without rebuilding
the display basis.
Examples — compile_fastpath.py and quadratic_get_tensor.py under
py/examples/ga/expression/.
Faster repeated evaluation — _check_blades no longer builds a full
BladeMask/display basis per binding; AffineExpression memoizes its
_union_masks/out_mask/_counting_axes_union; and the fully-bound
MV/scalar path precomputes the einsum layout and a greedy contraction path
once, reusing them on every call.