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.

For more information, see: https://wiki.haskell.org/Cabal/NewBuild

Resolving dependencies...
Starting     regex-base-0.94.0.0
Building     regex-base-0.94.0.0
Completed    regex-base-0.94.0.0
Downloading  regex-pcre-builtin-0.95.1.1.8.43
Downloaded   regex-pcre-builtin-0.95.1.1.8.43
Starting     regex-pcre-builtin-0.95.1.1.8.43
Building     regex-pcre-builtin-0.95.1.1.8.43
Completed    regex-pcre-builtin-0.95.1.1.8.43