This PR modifies pretty printing of `fun` binders, suppressing the safe
shadowing feature among the binders in the same `fun`. For example,
rather than pretty printing as `fun x x => 0`, we now see `fun x x_1 =>
0`. The calculation is done per `fun`, so for example `fun x => id fun x
=> 0` pretty prints as-is, taking advantage of safe shadowing.
The motivation for this change is that many users have reported that
safe shadowing within the same `fun` is confusing.
This PR fixes an issue where private definitions recursively invoked
using generalized field notation (dot notation) would give an "invalid
field" errors. It also fixes an issue where "invalid field notation"
errors would pretty print the name of the declaration with a `_private`
prefix.
Closes#10044
This PR improves the error messages produced by invalid projections and
field notation. It also adds a hint to the "function expected" error
message noting the argument to which the term is being applied, which
can be helpful for debugging spurious "function expected" messages
actually caused by syntax errors.
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Co-authored-by: Joachim Breitner <mail@joachim-breitner.de>
