# Module Migrate_parsetree_versions.OCaml_403

    module OCaml_403: OCaml_version  with module Ast = Ast_403

    module Ast: Migrate_parsetree_versions.Ast

Ast definition for this version

    val version : int

    val string_version : string

    type types = < case : Migrate_parsetree_versions.Ast.Parsetree.case;
             core_type : Migrate_parsetree_versions.Ast.Parsetree.core_type;
             expression : Migrate_parsetree_versions.Ast.Parsetree.expression;
             extension_constructor : Migrate_parsetree_versions.Ast.Parsetree.extension_constructor;
             mapper : Migrate_parsetree_versions.Ast.Ast_mapper.mapper;
             out_class_type : Migrate_parsetree_versions.Ast.Outcometree.out_class_type;
             out_module_type : Migrate_parsetree_versions.Ast.Outcometree.out_module_type;
             out_phrase : Migrate_parsetree_versions.Ast.Outcometree.out_phrase;
             out_sig_item : Migrate_parsetree_versions.Ast.Outcometree.out_sig_item;
             out_type : Migrate_parsetree_versions.Ast.Outcometree.out_type;
             out_type_extension : Migrate_parsetree_versions.Ast.Outcometree.out_type_extension;
             out_value : Migrate_parsetree_versions.Ast.Outcometree.out_value;
             pattern : Migrate_parsetree_versions.Ast.Parsetree.pattern;
             signature : Migrate_parsetree_versions.Ast.Parsetree.signature;
             structure : Migrate_parsetree_versions.Ast.Parsetree.structure;
             toplevel_phrase : Migrate_parsetree_versions.Ast.Parsetree.toplevel_phrase;
             type_declaration : Migrate_parsetree_versions.Ast.Parsetree.type_declaration;
             type_extension : Migrate_parsetree_versions.Ast.Parsetree.type_extension >
           Migrate_parsetree_versions._types

Shortcut for talking about Ast types

    type '_ Migrate_parsetree_versions.witnesses +=

`|` | `Version : `types Migrate_parsetree_versions.witnesses``

A construtor for recovering type equalities between two arbitrary versions.

    val migration_info : types
           Migrate_parsetree_versions.migration_info

Information used to derive migration functions, see below