Closes#1185.
This mostly reverts "Add support for multi-`let` (#675)" /
8a5bfaa3b9.
Also:
* Add fields for Src
This is useful for to make 'Note's less noisy during debugging:
first srcText expr
This reduces the runtime of the `deep-nested-large-record` benchmark by about 50%.
Note that previously, contrary to its name and documentation, this function traversed a Dhall.Map in insertion order due to its use of Dhall.Map.toList! With this change, the traversal is changed to ascending key order.
Also:
- Fix the deep-nested-large-record benchmark
- Remove the map-operations benchmark: This benchmark actually reports a ~20% loss of performance for the unorderedTraverseWithKey_ change. Since we eventually care about dhall's performance we it's better not to be mislead by a questionable micro-benchmark.
The motivation for this change is:
* To catch build failures in downstream packages whenever we make a breaking
change to the `dhall` API
* To reduce the amount of work I need in order to cut a release for all of
these packages
* To better share Nix/CI-related logic between the projects
Note that I have not yet migrated `dhall-nix` in. I'm waiting for
https://github.com/dhall-lang/dhall-nix/issues/17 to be fixed since
`dhall-nix` is incompatible with later versions of `megaparsec` due to
`hnix`.
