until -package:numeric-prelude -package:language-bash -package:clash-prelude -package:utility-ht -package:Cabal -package:conferer -package:base-prelude -package:rebase -package:ghc -package:selective 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.