* Make properties on NamespacedKeyword/NamespacedSymbol private
* Use only a single String for NamespacedKeyword/NamespacedSymbol
* Review comments.
* Remove unsafe code in namespaced_name.
Benchmarking shows approximately zero change.
* Allow the types of ns and name to differ when constructing a NamespacedName.
* Make symbol namespaces optional.
* Normalize names of keyword/symbol constructors.
This will make the subsequent refactor much less painful.
* Use expect not unwrap.
* Merge Keyword and NamespacedKeyword.
We were forgetting to check for bound variables when resolving types other than ref types during inequality handling. This patch adds in the binding checks and `bails` if the bound variable is of the wrong type. #634
This puts caching in mentat_db, adds a reverse lookup capability for
unique attributes, and populates bidirectional caches with a single
SQL cursor walk.
Differentiate between begin_read and begin_uncached_read.
Note that we still allow toggling within InProgress, because there might be
transient local state that makes starting a new transaction impossible.
