rust/src/librustsyntax/fold.rs
2012-05-04 12:33:08 -07:00

814 lines
31 KiB
Rust

import codemap::span;
import ast::*;
export ast_fold_precursor;
export ast_fold;
export default_ast_fold;
export make_fold;
export noop_fold_crate;
export noop_fold_item;
export noop_fold_expr;
export noop_fold_pat;
export noop_fold_mod;
export noop_fold_ty;
export noop_fold_block;
export wrap;
export fold_ty_param;
export fold_ty_params;
export fold_fn_decl;
type ast_fold = @mut a_f;
// We may eventually want to be able to fold over type parameters, too
type ast_fold_precursor =
//unlike the others, item_ is non-trivial
{fold_crate: fn@(crate_, span, ast_fold) -> (crate_, span),
fold_crate_directive: fn@(crate_directive_, span,
ast_fold) -> (crate_directive_, span),
fold_view_item: fn@(view_item_, ast_fold) -> view_item_,
fold_native_item: fn@(&&@native_item, ast_fold) -> @native_item,
fold_item: fn@(&&@item, ast_fold) -> @item,
fold_class_item: fn@(&&@class_member, ast_fold) -> @class_member,
fold_item_underscore: fn@(item_, ast_fold) -> item_,
fold_method: fn@(&&@method, ast_fold) -> @method,
fold_block: fn@(blk_, span, ast_fold) -> (blk_, span),
fold_stmt: fn@(stmt_, span, ast_fold) -> (stmt_, span),
fold_arm: fn@(arm, ast_fold) -> arm,
fold_pat: fn@(pat_, span, ast_fold) -> (pat_, span),
fold_decl: fn@(decl_, span, ast_fold) -> (decl_, span),
fold_expr: fn@(expr_, span, ast_fold) -> (expr_, span),
fold_ty: fn@(ty_, span, ast_fold) -> (ty_, span),
fold_constr: fn@(ast::constr_, span, ast_fold) -> (constr_, span),
fold_ty_constr: fn@(ast::ty_constr_, span, ast_fold)
-> (ty_constr_, span),
fold_mod: fn@(_mod, ast_fold) -> _mod,
fold_native_mod: fn@(native_mod, ast_fold) -> native_mod,
fold_variant: fn@(variant_, span, ast_fold) -> (variant_, span),
fold_ident: fn@(&&ident, ast_fold) -> ident,
fold_path: fn@(path, ast_fold) -> path,
fold_local: fn@(local_, span, ast_fold) -> (local_, span),
map_exprs: fn@(fn@(&&@expr) -> @expr, [@expr]) -> [@expr],
new_id: fn@(node_id) -> node_id,
new_span: fn@(span) -> span};
type a_f =
{fold_crate: fn@(crate) -> crate,
fold_crate_directive: fn@(&&@crate_directive) -> @crate_directive,
fold_view_item: fn@(&&@view_item) -> @view_item,
fold_native_item: fn@(&&@native_item) -> @native_item,
fold_item: fn@(&&@item) -> @item,
fold_class_item: fn@(&&@class_member) -> @class_member,
fold_item_underscore: fn@(item_) -> item_,
fold_method: fn@(&&@method) -> @method,
fold_block: fn@(blk) -> blk,
fold_stmt: fn@(&&@stmt) -> @stmt,
fold_arm: fn@(arm) -> arm,
fold_pat: fn@(&&@pat) -> @pat,
fold_decl: fn@(&&@decl) -> @decl,
fold_expr: fn@(&&@expr) -> @expr,
fold_ty: fn@(&&@ty) -> @ty,
fold_constr: fn@(&&@constr) -> @constr,
fold_ty_constr: fn@(&&@ty_constr) -> @ty_constr,
fold_mod: fn@(_mod) -> _mod,
fold_native_mod: fn@(native_mod) -> native_mod,
fold_variant: fn@(variant) -> variant,
fold_ident: fn@(&&ident) -> ident,
fold_path: fn@(&&@path) -> @path,
fold_local: fn@(&&@local) -> @local,
map_exprs: fn@(fn@(&&@expr) -> @expr, [@expr]) -> [@expr],
new_id: fn@(node_id) -> node_id,
new_span: fn@(span) -> span};
//fn nf_dummy<T>(&T node) -> T { fail; }
fn nf_crate_dummy(_c: crate) -> crate { fail; }
fn nf_crate_directive_dummy(&&_c: @crate_directive) -> @crate_directive {
fail;
}
fn nf_view_item_dummy(&&_v: @view_item) -> @view_item { fail; }
fn nf_native_item_dummy(&&_n: @native_item) -> @native_item { fail; }
fn nf_item_dummy(&&_i: @item) -> @item { fail; }
fn nf_class_item_dummy(&&_ci: @class_member) -> @class_member { fail; }
fn nf_item_underscore_dummy(_i: item_) -> item_ { fail; }
fn nf_method_dummy(&&_m: @method) -> @method { fail; }
fn nf_blk_dummy(_b: blk) -> blk { fail; }
fn nf_stmt_dummy(&&_s: @stmt) -> @stmt { fail; }
fn nf_arm_dummy(_a: arm) -> arm { fail; }
fn nf_pat_dummy(&&_p: @pat) -> @pat { fail; }
fn nf_decl_dummy(&&_d: @decl) -> @decl { fail; }
fn nf_expr_dummy(&&_e: @expr) -> @expr { fail; }
fn nf_ty_dummy(&&_t: @ty) -> @ty { fail; }
fn nf_constr_dummy(&&_c: @constr) -> @constr { fail; }
fn nf_ty_constr_dummy(&&_c: @ty_constr) -> @ty_constr { fail; }
fn nf_mod_dummy(_m: _mod) -> _mod { fail; }
fn nf_native_mod_dummy(_n: native_mod) -> native_mod { fail; }
fn nf_variant_dummy(_v: variant) -> variant { fail; }
fn nf_ident_dummy(&&_i: ident) -> ident { fail; }
fn nf_path_dummy(&&_p: @path) -> @path { fail; }
fn nf_local_dummy(&&_o: @local) -> @local { fail; }
/* some little folds that probably aren't useful to have in ast_fold itself*/
//used in noop_fold_item and noop_fold_crate and noop_fold_crate_directive
fn fold_meta_item_(&&mi: @meta_item, fld: ast_fold) -> @meta_item {
ret @{node:
alt mi.node {
meta_word(id) { meta_word(fld.fold_ident(id)) }
meta_list(id, mis) {
let fold_meta_item = bind fold_meta_item_(_, fld);
meta_list(id, vec::map(mis, fold_meta_item))
}
meta_name_value(id, s) {
meta_name_value(fld.fold_ident(id), s)
}
},
span: fld.new_span(mi.span)};
}
//used in noop_fold_item and noop_fold_crate
fn fold_attribute_(at: attribute, fld: ast_fold) ->
attribute {
ret {node: {style: at.node.style,
value: *fold_meta_item_(@at.node.value, fld)},
span: fld.new_span(at.span)};
}
//used in noop_fold_native_item and noop_fold_fn_decl
fn fold_arg_(a: arg, fld: ast_fold) -> arg {
ret {mode: a.mode,
ty: fld.fold_ty(a.ty),
ident: fld.fold_ident(a.ident),
id: fld.new_id(a.id)};
}
//used in noop_fold_expr, and possibly elsewhere in the future
fn fold_mac_(m: mac, fld: ast_fold) -> mac {
ret {node:
alt m.node {
mac_invoc(pth, arg, body) {
mac_invoc(fld.fold_path(pth),
option::map(arg, fld.fold_expr), body)
}
mac_embed_type(ty) { mac_embed_type(fld.fold_ty(ty)) }
mac_embed_block(blk) { mac_embed_block(fld.fold_block(blk)) }
mac_ellipsis { mac_ellipsis }
mac_aq(_,_) { /* fixme */ m.node }
mac_var(_) { /* fixme */ m.node }
},
span: fld.new_span(m.span)};
}
fn fold_fn_decl(decl: ast::fn_decl, fld: ast_fold) -> ast::fn_decl {
ret {inputs: vec::map(decl.inputs, bind fold_arg_(_, fld)),
output: fld.fold_ty(decl.output),
purity: decl.purity,
cf: decl.cf,
constraints: vec::map(decl.constraints, fld.fold_constr)}
}
fn fold_ty_param_bound(tpb: ty_param_bound, fld: ast_fold) -> ty_param_bound {
alt tpb {
bound_copy | bound_send { tpb }
bound_iface(ty) { bound_iface(fld.fold_ty(ty)) }
}
}
fn fold_ty_param(tp: ty_param, fld: ast_fold) -> ty_param {
{ident: tp.ident,
id: fld.new_id(tp.id),
bounds: @vec::map(*tp.bounds, fold_ty_param_bound(_, fld))}
}
fn fold_ty_params(tps: [ty_param], fld: ast_fold) -> [ty_param] {
vec::map(tps, fold_ty_param(_, fld))
}
fn noop_fold_crate(c: crate_, fld: ast_fold) -> crate_ {
let fold_meta_item = bind fold_meta_item_(_, fld);
let fold_attribute = bind fold_attribute_(_, fld);
ret {directives: vec::map(c.directives, fld.fold_crate_directive),
module: fld.fold_mod(c.module),
attrs: vec::map(c.attrs, fold_attribute),
config: vec::map(c.config, fold_meta_item)};
}
fn noop_fold_crate_directive(cd: crate_directive_, fld: ast_fold) ->
crate_directive_ {
ret alt cd {
cdir_src_mod(id, attrs) {
cdir_src_mod(fld.fold_ident(id), attrs)
}
cdir_dir_mod(id, cds, attrs) {
cdir_dir_mod(fld.fold_ident(id),
vec::map(cds, fld.fold_crate_directive), attrs)
}
cdir_view_item(vi) { cdir_view_item(fld.fold_view_item(vi)) }
cdir_syntax(_) { cd }
}
}
fn noop_fold_view_item(vi: view_item_, _fld: ast_fold) -> view_item_ {
ret vi;
}
fn noop_fold_native_item(&&ni: @native_item, fld: ast_fold) -> @native_item {
let fold_arg = bind fold_arg_(_, fld);
let fold_attribute = bind fold_attribute_(_, fld);
ret @{ident: fld.fold_ident(ni.ident),
attrs: vec::map(ni.attrs, fold_attribute),
node:
alt ni.node {
native_item_fn(fdec, typms) {
native_item_fn({inputs: vec::map(fdec.inputs, fold_arg),
output: fld.fold_ty(fdec.output),
purity: fdec.purity,
cf: fdec.cf,
constraints:
vec::map(fdec.constraints,
fld.fold_constr)},
fold_ty_params(typms, fld))
}
},
id: fld.new_id(ni.id),
span: fld.new_span(ni.span)};
}
fn noop_fold_item(&&i: @item, fld: ast_fold) -> @item {
let fold_attribute = bind fold_attribute_(_, fld);
ret @{ident: fld.fold_ident(i.ident),
attrs: vec::map(i.attrs, fold_attribute),
id: fld.new_id(i.id),
node: fld.fold_item_underscore(i.node),
span: fld.new_span(i.span)};
}
fn noop_fold_class_item(&&ci: @class_member, fld: ast_fold)
-> @class_member {
@{node: alt ci.node {
instance_var(ident, t, cm, id, p) {
instance_var(ident, fld.fold_ty(t), cm, id, p)
}
class_method(m) { class_method(fld.fold_method(m)) }
},
span: ci.span}
}
fn noop_fold_item_underscore(i: item_, fld: ast_fold) -> item_ {
ret alt i {
item_const(t, e) { item_const(fld.fold_ty(t), fld.fold_expr(e)) }
item_fn(decl, typms, body) {
item_fn(fold_fn_decl(decl, fld),
fold_ty_params(typms, fld),
fld.fold_block(body))
}
item_mod(m) { item_mod(fld.fold_mod(m)) }
item_native_mod(nm) { item_native_mod(fld.fold_native_mod(nm)) }
item_ty(t, typms, rp) { item_ty(fld.fold_ty(t),
fold_ty_params(typms, fld),
rp) }
item_enum(variants, typms, r) {
item_enum(vec::map(variants, fld.fold_variant),
fold_ty_params(typms, fld),
r)
}
item_class(typms, ifaces, items, ctor, rp) {
let ctor_body = fld.fold_block(ctor.node.body);
let ctor_decl = fold_fn_decl(ctor.node.dec, fld);
let ctor_id = fld.new_id(ctor.node.id);
item_class(
typms,
vec::map(ifaces, {|p| fold_iface_ref(p, fld) }),
vec::map(items, fld.fold_class_item),
{node: {body: ctor_body,
dec: ctor_decl,
id: ctor_id with ctor.node}
with ctor},
rp)
}
item_impl(tps, rp, ifce, ty, methods) {
item_impl(fold_ty_params(tps, fld),
rp,
ifce.map { |p| fold_iface_ref(p, fld) },
fld.fold_ty(ty),
vec::map(methods, fld.fold_method))
}
item_iface(tps, rp, methods) {
item_iface(fold_ty_params(tps, fld),
rp,
methods)
}
item_res(decl, typms, body, did, cid, rp) {
item_res(fold_fn_decl(decl, fld),
fold_ty_params(typms, fld),
fld.fold_block(body),
fld.new_id(did),
fld.new_id(cid),
rp)
}
};
}
fn fold_iface_ref(&&p: @iface_ref, fld: ast_fold) -> @iface_ref {
@{path: fld.fold_path(p.path), id: fld.new_id(p.id)}
}
fn noop_fold_method(&&m: @method, fld: ast_fold) -> @method {
ret @{ident: fld.fold_ident(m.ident),
attrs: m.attrs,
tps: fold_ty_params(m.tps, fld),
decl: fold_fn_decl(m.decl, fld),
body: fld.fold_block(m.body),
id: fld.new_id(m.id),
span: fld.new_span(m.span),
self_id: fld.new_id(m.self_id),
privacy: m.privacy};
}
fn noop_fold_block(b: blk_, fld: ast_fold) -> blk_ {
ret {view_items: vec::map(b.view_items, fld.fold_view_item),
stmts: vec::map(b.stmts, fld.fold_stmt),
expr: option::map(b.expr, fld.fold_expr),
id: fld.new_id(b.id),
rules: b.rules};
}
fn noop_fold_stmt(s: stmt_, fld: ast_fold) -> stmt_ {
ret alt s {
stmt_decl(d, nid) { stmt_decl(fld.fold_decl(d), fld.new_id(nid)) }
stmt_expr(e, nid) { stmt_expr(fld.fold_expr(e), fld.new_id(nid)) }
stmt_semi(e, nid) { stmt_semi(fld.fold_expr(e), fld.new_id(nid)) }
};
}
fn noop_fold_arm(a: arm, fld: ast_fold) -> arm {
ret {pats: vec::map(a.pats, fld.fold_pat),
guard: option::map(a.guard, fld.fold_expr),
body: fld.fold_block(a.body)};
}
fn noop_fold_pat(p: pat_, fld: ast_fold) -> pat_ {
ret alt p {
pat_wild { p }
pat_ident(pth, sub) {
pat_ident(fld.fold_path(pth), option::map(sub, fld.fold_pat))
}
pat_lit(e) { pat_lit(fld.fold_expr(e)) }
pat_enum(pth, pats) {
pat_enum(fld.fold_path(pth), option::map(pats)
{|pats| vec::map(pats, fld.fold_pat)})
}
pat_rec(fields, etc) {
let mut fs = [];
for fields.each {|f|
fs += [{ident: f.ident, pat: fld.fold_pat(f.pat)}];
}
pat_rec(fs, etc)
}
pat_tup(elts) { pat_tup(vec::map(elts, fld.fold_pat)) }
pat_box(inner) { pat_box(fld.fold_pat(inner)) }
pat_uniq(inner) { pat_uniq(fld.fold_pat(inner)) }
pat_range(e1, e2) {
pat_range(fld.fold_expr(e1), fld.fold_expr(e2))
}
};
}
fn noop_fold_decl(d: decl_, fld: ast_fold) -> decl_ {
alt d {
decl_local(ls) { decl_local(vec::map(ls, fld.fold_local)) }
decl_item(it) { decl_item(fld.fold_item(it)) }
}
}
fn wrap<T>(f: fn@(T, ast_fold) -> T)
-> fn@(T, span, ast_fold) -> (T, span)
{
ret fn@(x: T, s: span, fld: ast_fold) -> (T, span) {
(f(x, fld), s)
}
}
fn noop_fold_expr(e: expr_, fld: ast_fold) -> expr_ {
fn fold_field_(field: field, fld: ast_fold) -> field {
ret {node:
{mutbl: field.node.mutbl,
ident: fld.fold_ident(field.node.ident),
expr: fld.fold_expr(field.node.expr)},
span: fld.new_span(field.span)};
}
let fold_field = bind fold_field_(_, fld);
let fold_mac = bind fold_mac_(_, fld);
ret alt e {
expr_new(p, i, v) {
expr_new(fld.fold_expr(p),
fld.new_id(i),
fld.fold_expr(v))
}
expr_vstore(e, v) {
expr_vstore(fld.fold_expr(e), v)
}
expr_vec(exprs, mutt) {
expr_vec(fld.map_exprs(fld.fold_expr, exprs), mutt)
}
expr_rec(fields, maybe_expr) {
expr_rec(vec::map(fields, fold_field),
option::map(maybe_expr, fld.fold_expr))
}
expr_tup(elts) { expr_tup(vec::map(elts, fld.fold_expr)) }
expr_call(f, args, blk) {
expr_call(fld.fold_expr(f), fld.map_exprs(fld.fold_expr, args),
blk)
}
expr_bind(f, args) {
let opt_map_se = bind option::map(_, fld.fold_expr);
expr_bind(fld.fold_expr(f), vec::map(args, opt_map_se))
}
expr_binary(binop, lhs, rhs) {
expr_binary(binop, fld.fold_expr(lhs), fld.fold_expr(rhs))
}
expr_unary(binop, ohs) { expr_unary(binop, fld.fold_expr(ohs)) }
expr_loop_body(f) { expr_loop_body(fld.fold_expr(f)) }
expr_lit(_) { e }
expr_cast(expr, ty) { expr_cast(fld.fold_expr(expr), ty) }
expr_addr_of(m, ohs) { expr_addr_of(m, fld.fold_expr(ohs)) }
expr_if(cond, tr, fl) {
expr_if(fld.fold_expr(cond), fld.fold_block(tr),
option::map(fl, fld.fold_expr))
}
expr_while(cond, body) {
expr_while(fld.fold_expr(cond), fld.fold_block(body))
}
expr_do_while(blk, expr) {
expr_do_while(fld.fold_block(blk), fld.fold_expr(expr))
}
expr_loop(body) {
expr_loop(fld.fold_block(body))
}
expr_alt(expr, arms, mode) {
expr_alt(fld.fold_expr(expr), vec::map(arms, fld.fold_arm), mode)
}
expr_fn(proto, decl, body, captures) {
expr_fn(proto, fold_fn_decl(decl, fld),
fld.fold_block(body), captures)
}
expr_fn_block(decl, body, captures) {
expr_fn_block(fold_fn_decl(decl, fld), fld.fold_block(body),
captures)
}
expr_block(blk) { expr_block(fld.fold_block(blk)) }
expr_move(el, er) {
expr_move(fld.fold_expr(el), fld.fold_expr(er))
}
expr_copy(e) { expr_copy(fld.fold_expr(e)) }
expr_assign(el, er) {
expr_assign(fld.fold_expr(el), fld.fold_expr(er))
}
expr_swap(el, er) {
expr_swap(fld.fold_expr(el), fld.fold_expr(er))
}
expr_assign_op(op, el, er) {
expr_assign_op(op, fld.fold_expr(el), fld.fold_expr(er))
}
expr_field(el, id, tys) {
expr_field(fld.fold_expr(el), fld.fold_ident(id),
vec::map(tys, fld.fold_ty))
}
expr_index(el, er) {
expr_index(fld.fold_expr(el), fld.fold_expr(er))
}
expr_path(pth) { expr_path(fld.fold_path(pth)) }
expr_fail(e) { expr_fail(option::map(e, fld.fold_expr)) }
expr_break | expr_cont { e }
expr_ret(e) { expr_ret(option::map(e, fld.fold_expr)) }
expr_be(e) { expr_be(fld.fold_expr(e)) }
expr_log(i, lv, e) { expr_log(i, fld.fold_expr(lv),
fld.fold_expr(e)) }
expr_assert(e) { expr_assert(fld.fold_expr(e)) }
expr_check(m, e) { expr_check(m, fld.fold_expr(e)) }
expr_if_check(cond, tr, fl) {
expr_if_check(fld.fold_expr(cond), fld.fold_block(tr),
option::map(fl, fld.fold_expr))
}
expr_mac(mac) { expr_mac(fold_mac(mac)) }
}
}
fn noop_fold_ty(t: ty_, fld: ast_fold) -> ty_ {
let fold_mac = bind fold_mac_(_, fld);
fn fold_mt(mt: mt, fld: ast_fold) -> mt {
{ty: fld.fold_ty(mt.ty), mutbl: mt.mutbl}
}
fn fold_field(f: ty_field, fld: ast_fold) -> ty_field {
{node: {ident: fld.fold_ident(f.node.ident),
mt: fold_mt(f.node.mt, fld)},
span: fld.new_span(f.span)}
}
alt t {
ty_nil | ty_bot {t}
ty_box(mt) {ty_box(fold_mt(mt, fld))}
ty_uniq(mt) {ty_uniq(fold_mt(mt, fld))}
ty_vec(mt) {ty_vec(fold_mt(mt, fld))}
ty_ptr(mt) {ty_ptr(fold_mt(mt, fld))}
ty_rptr(region, mt) {ty_rptr(region, fold_mt(mt, fld))}
ty_rec(fields) {ty_rec(vec::map(fields) {|f| fold_field(f, fld)})}
ty_fn(proto, decl) {ty_fn(proto, fold_fn_decl(decl, fld))}
ty_tup(tys) {ty_tup(vec::map(tys) {|ty| fld.fold_ty(ty)})}
ty_path(path, id) {ty_path(fld.fold_path(path), fld.new_id(id))}
ty_constr(ty, constrs) {ty_constr(fld.fold_ty(ty),
vec::map(constrs, fld.fold_ty_constr))}
ty_vstore(t, vs) {ty_vstore(fld.fold_ty(t), vs)}
ty_mac(mac) {ty_mac(fold_mac(mac))}
ty_infer {t}
}
}
fn noop_fold_constr(c: constr_, fld: ast_fold) -> constr_ {
{path: fld.fold_path(c.path), args: c.args, id: fld.new_id(c.id)}
}
fn noop_fold_ty_constr(c: ty_constr_, fld: ast_fold) -> ty_constr_ {
let rslt: ty_constr_ =
{path: fld.fold_path(c.path), args: c.args, id: fld.new_id(c.id)};
rslt
}
// ...nor do modules
fn noop_fold_mod(m: _mod, fld: ast_fold) -> _mod {
ret {view_items: vec::map(m.view_items, fld.fold_view_item),
items: vec::map(m.items, fld.fold_item)};
}
fn noop_fold_native_mod(nm: native_mod, fld: ast_fold) -> native_mod {
ret {view_items: vec::map(nm.view_items, fld.fold_view_item),
items: vec::map(nm.items, fld.fold_native_item)}
}
fn noop_fold_variant(v: variant_, fld: ast_fold) -> variant_ {
fn fold_variant_arg_(va: variant_arg, fld: ast_fold) -> variant_arg {
ret {ty: fld.fold_ty(va.ty), id: fld.new_id(va.id)};
}
let fold_variant_arg = bind fold_variant_arg_(_, fld);
let args = vec::map(v.args, fold_variant_arg);
let fold_attribute = bind fold_attribute_(_, fld);
let attrs = vec::map(v.attrs, fold_attribute);
let de = alt v.disr_expr {
some(e) {some(fld.fold_expr(e))}
none {none}
};
ret {name: v.name,
attrs: attrs,
args: args, id: fld.new_id(v.id),
disr_expr: de};
}
fn noop_fold_ident(&&i: ident, _fld: ast_fold) -> ident { ret i; }
fn noop_fold_path(&&p: path, fld: ast_fold) -> path {
ret {span: fld.new_span(p.span), global: p.global,
idents: vec::map(p.idents, fld.fold_ident),
rp: p.rp,
types: vec::map(p.types, fld.fold_ty)};
}
fn noop_fold_local(l: local_, fld: ast_fold) -> local_ {
ret {is_mutbl: l.is_mutbl,
ty: fld.fold_ty(l.ty),
pat: fld.fold_pat(l.pat),
init:
alt l.init {
option::none::<initializer> { l.init }
option::some::<initializer>(init) {
option::some::<initializer>({op: init.op,
expr: fld.fold_expr(init.expr)})
}
},
id: fld.new_id(l.id)};
}
/* temporarily eta-expand because of a compiler bug with using `fn<T>` as a
value */
fn noop_map_exprs(f: fn@(&&@expr) -> @expr, es: [@expr]) -> [@expr] {
ret vec::map(es, f);
}
fn noop_id(i: node_id) -> node_id { ret i; }
fn noop_span(sp: span) -> span { ret sp; }
fn default_ast_fold() -> @ast_fold_precursor {
ret @{fold_crate: wrap(noop_fold_crate),
fold_crate_directive: wrap(noop_fold_crate_directive),
fold_view_item: noop_fold_view_item,
fold_native_item: noop_fold_native_item,
fold_item: noop_fold_item,
fold_class_item: noop_fold_class_item,
fold_item_underscore: noop_fold_item_underscore,
fold_method: noop_fold_method,
fold_block: wrap(noop_fold_block),
fold_stmt: wrap(noop_fold_stmt),
fold_arm: noop_fold_arm,
fold_pat: wrap(noop_fold_pat),
fold_decl: wrap(noop_fold_decl),
fold_expr: wrap(noop_fold_expr),
fold_ty: wrap(noop_fold_ty),
fold_constr: wrap(noop_fold_constr),
fold_ty_constr: wrap(noop_fold_ty_constr),
fold_mod: noop_fold_mod,
fold_native_mod: noop_fold_native_mod,
fold_variant: wrap(noop_fold_variant),
fold_ident: noop_fold_ident,
fold_path: noop_fold_path,
fold_local: wrap(noop_fold_local),
map_exprs: noop_map_exprs,
new_id: noop_id,
new_span: noop_span};
}
fn make_fold(afp: ast_fold_precursor) -> ast_fold {
// FIXME: Have to bind all the bare functions into shared functions
// because @mut is invariant with respect to its contents
// I assume this has something to do with Issue #1973 - tjc
let result: ast_fold =
@mut {fold_crate: bind nf_crate_dummy(_),
fold_crate_directive: bind nf_crate_directive_dummy(_),
fold_view_item: bind nf_view_item_dummy(_),
fold_native_item: bind nf_native_item_dummy(_),
fold_item: bind nf_item_dummy(_),
fold_class_item: bind nf_class_item_dummy(_),
fold_item_underscore: bind nf_item_underscore_dummy(_),
fold_method: bind nf_method_dummy(_),
fold_block: bind nf_blk_dummy(_),
fold_stmt: bind nf_stmt_dummy(_),
fold_arm: bind nf_arm_dummy(_),
fold_pat: bind nf_pat_dummy(_),
fold_decl: bind nf_decl_dummy(_),
fold_expr: bind nf_expr_dummy(_),
fold_ty: bind nf_ty_dummy(_),
fold_constr: bind nf_constr_dummy(_),
fold_ty_constr: bind nf_ty_constr_dummy(_),
fold_mod: bind nf_mod_dummy(_),
fold_native_mod: bind nf_native_mod_dummy(_),
fold_variant: bind nf_variant_dummy(_),
fold_ident: bind nf_ident_dummy(_),
fold_path: bind nf_path_dummy(_),
fold_local: bind nf_local_dummy(_),
map_exprs: bind noop_map_exprs(_, _),
new_id: bind noop_id(_),
new_span: bind noop_span(_)};
/* naturally, a macro to write these would be nice */
fn f_crate(afp: ast_fold_precursor, f: ast_fold, c: crate) -> crate {
let (n, s) = afp.fold_crate(c.node, c.span, f);
ret {node: n, span: afp.new_span(s)};
}
fn f_crate_directive(afp: ast_fold_precursor, f: ast_fold,
&&c: @crate_directive) -> @crate_directive {
let (n, s) = afp.fold_crate_directive(c.node, c.span, f);
ret @{node: n,
span: afp.new_span(s)};
}
fn f_view_item(afp: ast_fold_precursor, f: ast_fold, &&x: @view_item) ->
@view_item {
ret @{node: afp.fold_view_item(x.node, f),
span: afp.new_span(x.span)};
}
fn f_native_item(afp: ast_fold_precursor, f: ast_fold, &&x: @native_item)
-> @native_item {
ret afp.fold_native_item(x, f);
}
fn f_item(afp: ast_fold_precursor, f: ast_fold, &&i: @item) -> @item {
ret afp.fold_item(i, f);
}
fn f_class_item(afp: ast_fold_precursor, f: ast_fold,
&&ci: @class_member) -> @class_member {
@{node: alt ci.node {
instance_var(nm, t, mt, id, p) {
instance_var(nm, f_ty(afp, f, t),
mt, id, p)
}
class_method(m) {
class_method(afp.fold_method(m, f))
}
}, span: afp.new_span(ci.span)}
}
fn f_item_underscore(afp: ast_fold_precursor, f: ast_fold, i: item_) ->
item_ {
ret afp.fold_item_underscore(i, f);
}
fn f_method(afp: ast_fold_precursor, f: ast_fold, &&x: @method)
-> @method {
ret afp.fold_method(x, f);
}
fn f_block(afp: ast_fold_precursor, f: ast_fold, x: blk) -> blk {
let (n, s) = afp.fold_block(x.node, x.span, f);
ret {node: n, span: afp.new_span(s)};
}
fn f_stmt(afp: ast_fold_precursor, f: ast_fold, &&x: @stmt) -> @stmt {
let (n, s) = afp.fold_stmt(x.node, x.span, f);
ret @{node: n, span: afp.new_span(s)};
}
fn f_arm(afp: ast_fold_precursor, f: ast_fold, x: arm) -> arm {
ret afp.fold_arm(x, f);
}
fn f_pat(afp: ast_fold_precursor, f: ast_fold, &&x: @pat) -> @pat {
let (n, s) = afp.fold_pat(x.node, x.span, f);
ret @{id: afp.new_id(x.id),
node: n,
span: afp.new_span(s)};
}
fn f_decl(afp: ast_fold_precursor, f: ast_fold, &&x: @decl) -> @decl {
let (n, s) = afp.fold_decl(x.node, x.span, f);
ret @{node: n, span: afp.new_span(s)};
}
fn f_expr(afp: ast_fold_precursor, f: ast_fold, &&x: @expr) -> @expr {
let (n, s) = afp.fold_expr(x.node, x.span, f);
ret @{id: afp.new_id(x.id),
node: n,
span: afp.new_span(s)};
}
fn f_ty(afp: ast_fold_precursor, f: ast_fold, &&x: @ty) -> @ty {
let (n, s) = afp.fold_ty(x.node, x.span, f);
ret @{id: afp.new_id(x.id), node: n, span: afp.new_span(s)};
}
fn f_constr(afp: ast_fold_precursor, f: ast_fold, &&x: @ast::constr) ->
@ast::constr {
let (n, s) = afp.fold_constr(x.node, x.span, f);
ret @{node: n, span: afp.new_span(s)};
}
fn f_ty_constr(afp: ast_fold_precursor, f: ast_fold,
&&x: @ast::ty_constr) ->
@ast::ty_constr {
let (n, s) : (ty_constr_, span) =
afp.fold_ty_constr(x.node, x.span, f);
ret @{node: n, span: afp.new_span(s)};
}
fn f_mod(afp: ast_fold_precursor, f: ast_fold, x: _mod) -> _mod {
ret afp.fold_mod(x, f);
}
fn f_native_mod(afp: ast_fold_precursor, f: ast_fold, x: native_mod) ->
native_mod {
ret afp.fold_native_mod(x, f);
}
fn f_variant(afp: ast_fold_precursor, f: ast_fold, x: variant) ->
variant {
let (n, s) = afp.fold_variant(x.node, x.span, f);
ret {node: n, span: afp.new_span(s)};
}
fn f_ident(afp: ast_fold_precursor, f: ast_fold, &&x: ident) -> ident {
ret afp.fold_ident(x, f);
}
fn f_path(afp: ast_fold_precursor, f: ast_fold, &&x: @path) -> @path {
@afp.fold_path(*x, f)
}
fn f_local(afp: ast_fold_precursor, f: ast_fold, &&x: @local) -> @local {
let (n, s) = afp.fold_local(x.node, x.span, f);
ret @{node: n, span: afp.new_span(s)};
}
*result =
{fold_crate: bind f_crate(afp, result, _),
fold_crate_directive: bind f_crate_directive(afp, result, _),
fold_view_item: bind f_view_item(afp, result, _),
fold_native_item: bind f_native_item(afp, result, _),
fold_item: bind f_item(afp, result, _),
fold_class_item: bind f_class_item(afp, result, _),
fold_item_underscore: bind f_item_underscore(afp, result, _),
fold_method: bind f_method(afp, result, _),
fold_block: bind f_block(afp, result, _),
fold_stmt: bind f_stmt(afp, result, _),
fold_arm: bind f_arm(afp, result, _),
fold_pat: bind f_pat(afp, result, _),
fold_decl: bind f_decl(afp, result, _),
fold_expr: bind f_expr(afp, result, _),
fold_ty: bind f_ty(afp, result, _),
fold_constr: bind f_constr(afp, result, _),
fold_ty_constr: bind f_ty_constr(afp, result, _),
fold_mod: bind f_mod(afp, result, _),
fold_native_mod: bind f_native_mod(afp, result, _),
fold_variant: bind f_variant(afp, result, _),
fold_ident: bind f_ident(afp, result, _),
fold_path: bind f_path(afp, result, _),
fold_local: bind f_local(afp, result, _),
map_exprs: afp.map_exprs,
new_id: afp.new_id,
new_span: afp.new_span};
ret result;
}
//
// Local Variables:
// mode: rust
// fill-column: 78;
// indent-tabs-mode: nil
// c-basic-offset: 4
// buffer-file-coding-system: utf-8-unix
// End:
//