From 82da31b3e0e9acdfbca4c48eb12ab1f28515ba10 Mon Sep 17 00:00:00 2001 From: Joey Hess Date: Wed, 9 Jul 2014 22:11:31 -0400 Subject: propellor (0.8.1) unstable; urgency=medium * Run apt-get update in initial bootstrap. * --list-fields now includes a table of fields that are not currently set, but would be used if they got set. * Remove .gitignore from cabal file list, to avoid build failure on Debian. Closes: #754334 # imported from the archive --- src/Utility/Data.hs | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) create mode 100644 src/Utility/Data.hs (limited to 'src/Utility/Data.hs') diff --git a/src/Utility/Data.hs b/src/Utility/Data.hs new file mode 100644 index 00000000..2df12b36 --- /dev/null +++ b/src/Utility/Data.hs @@ -0,0 +1,17 @@ +{- utilities for simple data types + - + - Copyright 2013 Joey Hess + - + - License: BSD-2-clause + -} + +module Utility.Data where + +{- First item in the list that is not Nothing. -} +firstJust :: Eq a => [Maybe a] -> Maybe a +firstJust ms = case dropWhile (== Nothing) ms of + [] -> Nothing + (md:_) -> md + +eitherToMaybe :: Either a b -> Maybe b +eitherToMaybe = either (const Nothing) Just -- cgit v1.3-2-g0d8e