OCaml tool: type sig -> list of names?

[zeroexcuses]

Is there an OCaml tool where as input, I specify a type sig, and as output, it give me a name. For example:

input: 'a list → ('a → 'b) → 'b list
output: List.map

input: 'a list → ('a → 'b option) → 'b list
output: List.filter_map

etc …
it’s fine if the output is more than one function

[nojb]

This is similar to Hoogle https://hoogle.haskell.org/ in the Haskell world. I know there are people interested in exploring this idea in OCaml, but as far as I know this doesn’t yet exist.

Cheers,
Nicolas

[Gopiandcode]

There are actually a couple such tools in the ecosystem that do this.

First of all, sherlodoc: https://doc.sherlocode.com/, which searches not only types but also documentation:

Fuzzy search in OCaml’s documentation for almost all opam packages.

• Search by name: concat map and Lwt pool
• Search by type with a colon: : list list -> list
• Search on name and type with a colon separator: Yojson : t -> string
• Search for constructors of a type: : Gg.color
• Use _ to omit a subtype and search for consumers of a type: : Gg.color -> _
• Products and reordering of arguments: : 'a list -> ('a * int -> bool) -> 'a list

Also, for a local tool, I think there’s dowsing: GitHub - Drup/dowsing: ᚛ A type of divination employed in attempts to locate identifiers matching a given type expression, although not sure it’s been released

$ search "'a list * 'a -> bool"
...
List.mem : 'a -> 'a list -> bool
...

$ search "'a list -> ('a * 'b -> 'b) -> 'b -> 'b"
...
List.fold_left :
  ('a -> 'b -> 'a) -> 'a -> 'b list -> 'a
List.fold_right :
  ('a -> 'b -> 'b) -> 'a list -> 'b -> 'b
...

[hyphenrf]

Also specific to the OCaml API, you can search by types in the manual… And Merlin offers a similar feature which I believe is project-wide… We already have step 1, a central package index, covered… Just need to consolidate these individual effots to give that index a good API search tool.

[nojb]

@Gopiandcode

First of all, sherlodoc: https://doc.sherlocode.com/,

Thanks! I wasn’t aware of it.

Cheers,
Nicolas

[UnixJunkie]

sherlocode just answered a query I had; I’ll start using it more.