ROADMAP.md

Stable Interface (v1.0)

• Make the entire library -safe-string compliant. This will involve introducing a Bytes module, removing all direct mutation on strings from the String module, and "re-typing" string values that require mutation to bytes.

• Do not export the \*\_intf modules from Base. Instead, any signatures should be exported by the .ml and .mlis.

• Only expose the first-class module interface of Hashtbl. Accompanying this should be cleanup of Hashtbl_intf, moving anything that's still required in core_kernel to the appropriate files in that project.

• Replace Hashtbl.create (module String) () by just Hashtbl.create (module String)

• Remove replace from Hashtbl_intf.Accessors.

• Label one of the arguments of Hashtbl_intf.merge_into to indicate the flow of data.

• Merge Hashtbl_intf.Key_common and Hashtbl_intf.Key_plain.

• Use Either.t as the return value for Map.partition.

• Rename Monad_intf.all_ignore to Monad_intf.all_unit.

• Eliminate all uses of Not_found, replacing them with descriptive error messages.

• Move the various private modules to Base.Base_private instead of Base.Exported_for_specific_uses and Base.Not_exposed_properly

• Use compare rather than cmp as the label for comparison functions throughout.

Implementation Cleanup

• Remove ignore and (=) from Sexp_conv's public interface. These values are hidden from the documentation so their removal won't be considered a breaking API change.

• Do not expose the type equality Int63_emul.W.t = int64.

• Replace the exception thrown by Float.of_string with a named exception that's more descriptive.

• Delete the Hashable toplevel module. This is a vestige of the previous Map and Set implementations and is no longer needed.

• Ensure that Map operations that are effective NO-OPs return the same Map.t they were provided. Candidate operations include e.g add, remove, filter.

• Simplify the implementation of Option.value_exn, if possible.

• Eliminate all instances of open! Polymorphic_compare

• Refactor common blit code in String.replace_all and String.replace_first.

• Delete unused function aliases in Import0

• Put Sexp_conv.Exn_converter into its own file, with only an alias in Sexp_conv, so that it doesn't get pulled unless used

• Create a file with all the basic types and their associated combinators (sexp_of_t, compare, hash), and expose the declaration

• Put all the exported private modules from Base.Exported_for_specific_uses and Base.Not_exposed_properly in Base.Base_private

• Decide on a better name for Polymorphic_compare. Polymorphic_compare_intf contains interface for comparison of non-polymorphic types, which is weird. Get rid of it and inline things in Comparable_intf

• hashtbl_of_sexp shouldn't live in Base.Sexp_conv since we have our own hash tables. Move it to sexplib

Performance Improvements

• In Hash_set.diff, use the size of each set to determine which to iterate over.

• Ensure that the correct compare function and other related functions are exported by all modules. These functions should not be derived from a functor application, in order to ensure proper inlining. Implementing this change should also include benchmarks to verify the initial result, and to maintain it on an ongoing basis. See bench/bench_int.ml for examples.

• Optimize Lazy.compare by performing a phys_equal check before forcing the lazy value. Note that this will also change the semantics of compare and should be documented and rolled out with care.

• Conduct a thorough performance review of the Sequence module.

Documentation

• Consolidate documentation the interface and implementation files related to the Hash module.

• Add documentation to the Ref toplevel module.

• Document properly how String.unescape_gen handles malformed strings

Changes For The Distant Future

• Make the various comparison functions return an Ordering.t instead of an int.