until -package:numeric-prelude -package:base-prelude -package:distribution-opensuse -package:extra -package:streaming -package:foundation -package:base -package:hedgehog -is:exact -package:IfElse package:dunai
Similar to Yampa's delayed switching. Loses a b in case of an
exception.
Run the first
msf until the second one produces
True
from the output of the first.