def pair.ok

cswap-bend-cli@0.1.0.0 · json/lex.bend:160

import Base

160# After \uD83D: is the next escape a \uDC00..\uDFFF low half?
161def pair.ok(+u1: U32, +t5: String) -> Bool:
162  is_hi(u1) && U32.is_eq(cc(t5, 0n), 92) && U32.is_eq(cc(t5, 1n), 117) && is_lo(hex4(String.drop(t5, 2n)))