def u32.first
import bend-kit-migrate@0.3.0.0/migrate.bend as Migrateimport Base
319def u32.first(+len: U32, r: Array<U32> & U32) -> Maybe<&2, U32>:
320 (a, +c) = r
321 +lead0 = U32.is_eq(c, 48) && U32.is_lt(1, len)
322 u32.go(U32.to_nat(len), (a, c), 0, 0, U32.is_lt(0, len) && U32.is_lt(len, 11) && Bool.not(lead0))