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[Laurent Thery <Laurent.Thery AT inria.fr>]

On 12/6/20 10:27 PM, Agnishom Chattopadhyay wrote:
> opam install coq-tactician

If you look at the dependency

opam info coq-tactician

depends:     "ocaml" {>= "4.08"}
             "dune" {>= "2.5"}
             "opam-client" {>= "2.1.0~beta2"}
             "cmdliner"
             "coq" {>= "8.12" & < "8.13~"}
             "coq-tactician-dummy"

more probably it comes from your ocaml version that could be too old and
you have to use the opam switch command

--
Laurent