def em.len
import bend-kit-zlib@0.5.1.0/zlib.bend as Zlibimport Base
import bend-kit-bits@0.1.0.1/bits.bend as Bits
798def em.len(w: Bits.Writer, +len: U32, c: Cx) -> Bits.Writer:
799 Cx{+i, +b, +e} = c
800 Bits.Writer.lsb(bw.code(w, fx.lit((i + 257 : U32))), e, (len - b : U32))