def hex.go

emerging-ezhttp@0.21.0.0 · src/http.bend:86

import Base

86# the hex digits at the front of a string, read until one is not a digit
87def hex.go(s: String, +acc: Nat) -> Nat:
88  match s:
89    case SNil{}:
90      acc
91    case SCon{+h, t}:
92      +v = hex.val(h)
93      hex.step(U32.is_ge(v, 16), acc,
94        _u => hex.go(t, Nat.add(Nat.mul(acc, 16n), U32.to_nat(v))))