Warning: The install command is a part of the legacy v1 style of cabal usage.

Please switch to using either the new project style and the new-install
command or the legacy v1-install alias as new-style projects will become the
default in the next version of cabal-install. Please file a bug if you cannot
replicate a working v1- use case with the new-style commands.

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Resolving dependencies...
cabal: Could not resolve dependencies:
[__0] trying: servant-cli-0.1.0.1 (user goal)
[__1] trying: warp-3.2.28 (dependency of servant-cli)
[__2] trying: http-date-0.0.8 (dependency of warp)
[__3] trying: attoparsec-0.13.2.2 (dependency of http-date)
[__4] trying: scientific-0.3.6.2 (dependency of attoparsec)
[__5] trying: primitive-0.7.0.0 (dependency of scientific)
[__6] trying: servant-server-0.16.1 (dependency of servant-cli)
[__7] next goal: aeson (dependency of servant-cli)
[__7] rejecting: aeson-1.4.3.0, aeson-1.4.2.0 (conflict: primitive==0.7.0.0,
aeson => primitive>=0.6.3.0 && <0.7)
[__7] rejecting: aeson-1.4.1.0 (conflict: primitive==0.7.0.0, aeson =>
primitive>=0.6.2.0 && <0.7)
[__7] rejecting: aeson-1.4.0.0, aeson-1.3.1.1, aeson-1.3.1.0, aeson-1.3.0.0,
aeson-1.2.4.0, aeson-1.2.3.0, aeson-1.2.2.0, aeson-1.2.1.0, aeson-1.2.0.0,
aeson-1.1.2.0, aeson-1.1.1.0, aeson-1.1.0.0, aeson-1.0.2.1, aeson-1.0.2.0,
aeson-1.0.1.0, aeson-1.0.0.0, aeson-0.11.3.0, aeson-0.11.2.1, aeson-0.11.2.0,
aeson-0.11.1.4, aeson-0.11.1.3, aeson-0.11.1.2, aeson-0.11.1.1,
aeson-0.11.1.0, aeson-0.11.0.0, aeson-0.9.0.1, aeson-0.9.0.0, aeson-0.8.1.1,
aeson-0.8.1.0, aeson-0.8.0.2, aeson-0.7.0.6, aeson-0.7.0.4, aeson-0.6.2.1,
aeson-0.6.2.0, aeson-0.6.1.0, aeson-0.6.0.2, aeson-0.6.0.1, aeson-0.6.0.0,
aeson-0.5.0.0, aeson-0.4.0.1, aeson-0.4.0.0, aeson-0.3.2.14, aeson-0.3.2.13,
aeson-0.3.2.12, aeson-0.3.2.11, aeson-0.3.2.10, aeson-0.3.2.9, aeson-0.3.2.8,
aeson-0.3.2.7, aeson-0.3.2.6, aeson-0.3.2.5, aeson-0.3.2.4, aeson-0.3.2.3,
aeson-0.3.2.2, aeson-0.3.2.1, aeson-0.3.2.0, aeson-0.3.1.1, aeson-0.3.1.0,
aeson-0.3.0.0, aeson-0.2.0.0, aeson-0.1.0.0, aeson-0.10.0.0, aeson-0.8.0.1,
aeson-0.8.0.0, aeson-0.7.0.5, aeson-0.7.0.3, aeson-0.7.0.2, aeson-0.7.0.1,
aeson-0.7.0.0 (conflict: servant-server => aeson>=1.4.1.0 && <1.5)
[__7] fail (backjumping, conflict set: aeson, primitive, servant-cli,
servant-server)
Backjump limit reached (currently 2000, change with --max-backjumps or try to
run with --reorder-goals).