Beloch.NumExact real algebraic numbers. A value is an exact rational Rat q (fast path: axioms 1–4 never leave ℚ), an element of a single extension of degree ≤ field_degree_cap Field {gen; coords} = coords(α) with α the root of the monic irreducible gen.mu isolated in (gen.lo, gen.hi) (fast path for axiom-5/6/7 roots, bpr2006 §12.4), or a general real algebraic number Qq backed by FLINT's qqbar (canonical minimal polynomial + certified ball; cross-field arithmetic, composite extensions). Invariant: Qq is irrational — rationals collapse to Rat. to_float is the only float, output-only. See decisions/0013-flint-qqbar-backend.md.
val zero : tval one : tval of_q : Q.t -> tval of_int : int -> tval refine_alg : Poly.t -> Q.t -> Q.t -> Q.t * Q.tval rational_roots_in : Poly.t -> Q.t -> Q.t -> Q.t listval poly_interval : Poly.t -> Q.t -> Q.t -> Q.t * Q.tval sign : t -> intval enclosure_tight : t -> Q.t -> Q.t * Q.tval to_float : t -> floatval to_rational_string : t -> string