Install this version:
emerge -a =dev-haskell/concurrent-output-1.10.21
If this version is masked, you can unmask it using the autounmask tool or standard emerge options:
autounmask =dev-haskell/concurrent-output-1.10.21
Or alternatively:
emerge --autounmask-write -a =dev-haskell/concurrent-output-1.10.21
# Copyright 1999-2026 Gentoo Authors
# Distributed under the terms of the GNU General Public License v2
EAPI=8
CABAL_FEATURES="lib profile haddock hoogle hscolour"
inherit haskell-cabal
DESCRIPTION="Ungarble output from several threads or commands"
HOMEPAGE="https://hackage.haskell.org/package/concurrent-output"
LICENSE="BSD-2"
SLOT="0/${PV}"
KEYWORDS="~amd64 ~x86"
RDEPEND="dev-haskell/ansi-terminal:=[profile?]
dev-haskell/async:=[profile?]
dev-haskell/terminal-size:=[profile?]
dev-haskell/text:=[profile?]
dev-lang/ghc:="
DEPEND="${RDEPEND}"
BDEPEND="dev-haskell/cabal:="
src_prepare() {
haskell-cabal_src_prepare
sed -i '/license-file/d' concurrent-output.cabal \
|| die "sed failed"
}
dev-haskell/ansi-terminal:=[profile?] dev-haskell/async:=[profile?] dev-haskell/terminal-size:=[profile?] dev-haskell/text:=[profile?] dev-lang/ghc:=
dev-haskell/ansi-terminal:=[profile?] dev-haskell/async:=[profile?] dev-haskell/terminal-size:=[profile?] dev-haskell/text:=[profile?] dev-lang/ghc:=
dev-haskell/cabal:=