This is a quite substantial tactic.
It also includes the infamour `NatCast` typeclass (which I've equipped
with a module-doc). I wasn't at all sure where that should live, so it
is currently randomly in `Lean/Elan/Tactic/NatCast.lean`: presumably if
we're doing this it will go somewhere in `Init`.
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Co-authored-by: Leonardo de Moura <leomoura@amazon.com>
This is pretty big PR that upstreams all of Std.Data.Int.Init in one go.
So far lemmas have seen minimal changes needed to adapt to Lean core
environment.
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Co-authored-by: Scott Morrison <scott.morrison@gmail.com>
This upstreams NatCast and IntCast alone independent of norm_cast in
#3322.
This will allow more efficiently upstreaming parts of Std.Data.Int
relevant for omega.
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Co-authored-by: Scott Morrison <scott.morrison@gmail.com>
