Perm.internal_length_eq: def of bend-mathlib@0.8.1.0
Import: import bend-mathlib@0.8.1.0/perm.bend as Perm
Lines 335-337 of bend-mathlib@0.8.1.0/perm.bend: https://jend.leeeet.dev/read.txt?path=bend-mathlib@0.8.1.0/perm.bend&start_line=335&end_line=337

import Base
import bendlib-kernel-list@1.0.0.0/list.bend as K

def internal_length_eq(-A: Data, +s: List<&2, Nat>, +xs: List<&2, A>, -ys: List<&2, A>, e: K.perm_steps(A, s, xs, ys)) -> {List.length(&2, A, ys) == List.length(&2, A, xs) : Nat}:
  %e : {List.length(&2, A, _) == List.length(&2, A, xs) : Nat}
  internal_apply_length(A, s, xs)

Uses (5):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List.length
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat
  https://jend.leeeet.dev/definition.txt?path=bend-mathlib@0.8.1.0/perm.bend&name=internal_apply_length
  https://jend.leeeet.dev/definition.txt?path=bendlib-kernel-list@1.0.0.0/list.bend&name=perm_steps