Query names

[d-winsor]

Given that names are internalized there is no easy way for users to use some of the efficient lookup methods that depend on them.

For example if the user has a namespace scope and wants to check if it has a function name "foo" they would need to iterate through the entire scope comparing the strings of each Overload's ipr::Name.

Something like the ability to query these internalize names so they can be used would be helpful:

class Lexicon {
  …
  Optional<String> query_string(std::string_view) const;
  Optional<Identifier> query_identifier(std::string_view) const;
  Optional<Operator> query_opterator(std::string_view) const;
}