Fast.low: def of lawful-bytes@0.1.1.0
Import: import lawful-bytes@0.1.1.0/fast.bend as Fast
Lines 31-37 of lawful-bytes@0.1.1.0/fast.bend: https://jend.leeeet.dev/read.txt?path=lawful-bytes@0.1.1.0/fast.bend&start_line=31&end_line=37

import Base

# The bytes of a word at or above byte i's place. The first word of a search
# sets the bytes below the start to 0xFF before the zero-byte test (not the
# flags after it): zb is exact only at its lowest zero byte, and a match below
# the start would otherwise borrow and flag the byte at the start (found by the
# proof agent: "A@BC" searched for 'A' from 1).
def low(+i: U32) -> U32:
  U32.shln(4294967295, U32.to_nat(((i .&. 3 : U32) << 3n : U32)))

Uses (4):
  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.shln
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32.to_nat