Module Ast_iterator

iterator allows to implement AST inspection using open recursion. A typical mapper would be based on default_iterator, a trivial iterator, and will fall back on it for handling the syntax it does not modify.

A generic Parsetree iterator

type iterator = {
attribute : iterator -> Parsetree.attribute -> unit;
attributes : iterator -> Parsetree.attribute list -> unit;
case : iterator -> Parsetree.case -> unit;
cases : iterator -> Parsetree.case list -> unit;
class_declaration : iterator -> Parsetree.class_declaration -> unit;
class_description : iterator -> Parsetree.class_description -> unit;
class_expr : iterator -> Parsetree.class_expr -> unit;
class_field : iterator -> Parsetree.class_field -> unit;
class_signature : iterator -> Parsetree.class_signature -> unit;
class_structure : iterator -> Parsetree.class_structure -> unit;
class_type : iterator -> Parsetree.class_type -> unit;
class_type_declaration : iterator -> Parsetree.class_type_declaration -> unit;
class_type_field : iterator -> Parsetree.class_type_field -> unit;
constructor_declaration : iterator -> Parsetree.constructor_declaration -> unit;
expr : iterator -> Parsetree.expression -> unit;
extension : iterator -> Parsetree.extension -> unit;
extension_constructor : iterator -> Parsetree.extension_constructor -> unit;
include_declaration : iterator -> Parsetree.include_declaration -> unit;
include_description : iterator -> Parsetree.include_description -> unit;
label_declaration : iterator -> Parsetree.label_declaration -> unit;
location : iterator -> Location.t -> unit;
module_binding : iterator -> Parsetree.module_binding -> unit;
module_declaration : iterator -> Parsetree.module_declaration -> unit;
module_expr : iterator -> Parsetree.module_expr -> unit;
module_type : iterator -> Parsetree.module_type -> unit;
module_type_declaration : iterator -> Parsetree.module_type_declaration -> unit;
open_description : iterator -> Parsetree.open_description -> unit;
pat : iterator -> Parsetree.pattern -> unit;
payload : iterator -> Parsetree.payload -> unit;
signature : iterator -> Parsetree.signature -> unit;
signature_item : iterator -> Parsetree.signature_item -> unit;
structure : iterator -> Parsetree.structure -> unit;
structure_item : iterator -> Parsetree.structure_item -> unit;
typ : iterator -> Parsetree.core_type -> unit;
type_declaration : iterator -> Parsetree.type_declaration -> unit;
type_extension : iterator -> Parsetree.type_extension -> unit;
type_kind : iterator -> Parsetree.type_kind -> unit;
value_binding : iterator -> Parsetree.value_binding -> unit;
value_description : iterator -> Parsetree.value_description -> unit;
with_constraint : iterator -> Parsetree.with_constraint -> unit;
}

A iterator record implements one "method" per syntactic category, using an open recursion style: each method takes as its first argument the iterator to be applied to children in the syntax tree.

val default_iterator : iterator

A default iterator, which implements a "do not do anything" mapping.