package ppx_core

AST traversal classes

To use these classes, inherit from them and override the methods corresponding to the types from Parsetree you want to process. For instance to collect all the string constants in a structure:

let string_constants_of = object
  inherit [string list] Ast_traverse.fold as super

  method! expression e acc =
    let acc = super#expression e acc in
    match e.pexp_desc with
    | Pexp_constant (Const_string (s, _)) -> s :: acc
    | _ -> acc

  method! pattern p acc =
    let acc = super#pattern p acc in
    match p.ppat_desc with
    | Ppat_constant (Const_string (s, _)) -> s :: acc
    | _ -> acc
end

let string_constants_of_structure = string_constants_of#structure