def huff.build.loop

gralha-bytes@0.1.0.1 · bytes.bend:174

import Base
import gralha-text-scan@0.1.0.1/scan.bend as U

174def huff.build.loop(+n: Nat, +lengths: Bytes, +index: U32, +codes: Bytes, +node: Huffman) -> Huffman:
175  match n:
176    case 0n: node
177    case 1n+d:
178      +len = bytes.get(lengths, index)
179      +word = bytes.get(codes, len)
180      U.branch(Huffman, U32.is_eq(len, 0), _ => huff.build.loop(d, lengths, U32.inc(index), codes, node),
181        _ => U.branch(Huffman, U32.is_le(len, 15) && U32.is_lt(word, U32.shln(1, U32.to_nat(len))), _ => huff.build.loop(d, lengths, U32.inc(index), bytes.set(codes, len, U32.inc(word)), huff.insert(node, U32.to_nat(len), word, index)), _ => HuffBad{}))