Generic.inv_go: def of bend-collections-laws-math@1.0.0.0
Import: import bend-collections-laws-math@1.0.0.0/src/math/generic.bend as Generic
Lines 567-576 of bend-collections-laws-math@1.0.0.0/src/math/generic.bend: https://jend.leeeet.dev/read.txt?path=bend-collections-laws-math@1.0.0.0/src/math/generic.bend&start_line=567&end_line=576

import Base
import bend-collections-laws-math@1.0.0.0/src/math/num.bend as N

# extended Euclid on (m, a mod m), keeping the coefficient of a mod m;
# st = (r1, r1 == 0)
def inv_go(~T: Data, ~op: N.Op<T> -> T, ~test: N.Test<T> -> Bool, fuel: Nat, +m: T, +r0: T, +s0: T, +s1: T, st: T & Bool) -> T & T:
  match fuel st:
    case 0n _:
      (r0, s0)
    case 1n+f Tuple{r1, True{}}:
      (r0, s0)
    case 1n+f Tuple{+r1, False{}}:
      inv_go(~T, ~op, ~test, f, m, r1, s1, inv_step(~T, ~op, ~test, m, op(N.Quot{r0, r1}), s0, s1), zst(~T, ~test, op(N.Rem{r0, r1})))

Uses (8):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Pair
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Sigma
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/src/math/generic.bend&name=inv_step
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/src/math/generic.bend&name=zst
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/src/math/num.bend&name=Op
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/src/math/num.bend&name=Test