`sig
type ast =
Impl :
(module Migrate_parsetree_versions.OCaml_version with type Ast.Parsetree.structure = 'concrete) *
'concrete -> Migrate_parsetree_ast_io.ast
| Intf :
(module Migrate_parsetree_versions.OCaml_version with type Ast.Parsetree.signature = 'concrete) *
'concrete -> Migrate_parsetree_ast_io.ast
type filename = string
type read_error = Not_a_binary_ast of string | Unknown_version of string
val from_channel :
Pervasives.in_channel ->
(Migrate_parsetree_ast_io.filename * Migrate_parsetree_ast_io.ast,
Migrate_parsetree_ast_io.read_error)
Pervasives.result
val from_bytes :
bytes ->
int ->
(Migrate_parsetree_ast_io.filename * Migrate_parsetree_ast_io.ast,
Migrate_parsetree_ast_io.read_error)
Pervasives.result
val to_channel :
Pervasives.out_channel ->
Migrate_parsetree_ast_io.filename -> Migrate_parsetree_ast_io.ast -> unit
val to_bytes :
Migrate_parsetree_ast_io.filename ->
Migrate_parsetree_ast_io.ast -> bytes
end`