PROOF.h_cat: def of bend-osdev-bytes@0.1.1.0
Import: import bend-osdev-bytes@0.1.1.0/PROOF.bend as PROOF
Lines 626-631 of bend-osdev-bytes@0.1.1.0/PROOF.bend: https://jend.leeeet.dev/read.txt?path=bend-osdev-bytes@0.1.1.0/PROOF.bend&start_line=626&end_line=631

import Base
import bend-osdev-bytes@0.1.1.0/bytes.bend as B

def h_cat(+xs: List<&2, U32>) -> {B.hex.cat(xs, SNil{}) == B.hex(xs) : String}:
  match xs:
    case Nil{}:
      {==}
    case Con{h, t}:
      Equal.cong(String, String, x => SCon{B.hex.digit(U32.shrn(B.byte(h), 4n)), SCon{B.hex.digit(U32.and(B.byte(h), 15)), x}}, B.hex.cat(t, SNil{}), B.hex(t), h_cat(t))

Uses (10):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Equal.cong
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=String
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32.and
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32.shrn
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-bytes@0.1.1.0/bytes.bend&name=byte
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-bytes@0.1.1.0/bytes.bend&name=hex
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-bytes@0.1.1.0/bytes.bend&name=hex.cat
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-bytes@0.1.1.0/bytes.bend&name=hex.digit