unison/unison-src/transcripts/update-type-turn-constructor-into-smart-constructor.md

.> builtins.merge
.> move.namespace builtin lib.builtin

unique type Foo = Bar Nat

makeFoo : Nat -> Foo
makeFoo n = Bar (n+10)

.> add

unique type Foo = internal.Bar Nat

Foo.Bar : Nat -> Foo
Foo.Bar n = internal.Bar n

.> update
.> view Foo
.> find.verbose