def tone_on
import cli@0.2.0.0/cli.bend as Cliimport Base
933# A skin tone after an emoji that takes one widens it to 2; any other is
934# 2 wide alone, as East Asian Wide.
935def tone_on(takes: Bool, narrow: Bool, join: Bool, code: U32) ->
936 WidthStep:
937 match takes:
938 case True{}:
939 WidthStep{Bool.pick(Nat, narrow, 1n, 0n), EmojiBase{code, False{}, join}}
940 case False{}: WidthStep{2n, EmojiNone{}}