Bonded.bond_neighbors_except_go: def of bend-prot@0.1.0.0
Import: import bend-prot@0.1.0.0/bonded.bend as Bonded
Lines 344-356 of bend-prot@0.1.0.0/bonded.bend: https://jend.leeeet.dev/read.txt?path=bend-prot@0.1.0.0/bonded.bend&start_line=344&end_line=356

import Base

# Angle auto-derivation from flat bonds: for each bond, fan over the other
# neighbors of each end. Needs no templates; duplicates across overlapping
# fans are possible in rings (documented, harmless for boolean use).
def bond_neighbors_except_go(bs: List<&2, U32>, +s: U32, +excl: U32, +acc: List<&2, U32>) -> List<&2, U32>:
  match bs:
    case Nil{}:
      List.reverse(&2, U32, acc)
    case x <> Nil{}:
      List.reverse(&2, U32, acc)
    case x <> y <> t:
      +x2 = x
      +y2 = y
      bond_neighbors_except_go(t, s, excl, Bool.pick(List<&2, U32>, U32.is_eq(x2, s), Bool.pick(List<&2, U32>, U32.is_eq(y2, excl), acc, y2 <> acc), Bool.pick(List<&2, U32>, U32.is_eq(y2, s), Bool.pick(List<&2, U32>, U32.is_eq(x2, excl), acc, x2 <> acc), acc)))

Uses (5):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool.pick
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List.reverse
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32.is_eq