1 // Copyright 2012 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
12 use driver::session::Session;
17 use syntax::codemap::dummy_sp;
19 use syntax::fold::ast_fold;
23 static STD_VERSION: &'static str = "0.9-pre";
25 pub fn maybe_inject_libstd_ref(sess: Session, crate: @ast::Crate)
28 inject_libstd_ref(sess, crate)
34 fn use_std(crate: &ast::Crate) -> bool {
35 !attr::contains_name(crate.attrs, "no_std")
38 fn no_prelude(attrs: &[ast::Attribute]) -> bool {
39 attr::contains_name(attrs, "no_implicit_prelude")
42 fn spanned<T>(x: T) -> codemap::Spanned<T> {
49 struct StandardLibraryInjector {
53 impl fold::ast_fold for StandardLibraryInjector {
54 fn fold_crate(&self, crate: &ast::Crate) -> ast::Crate {
55 let version = STD_VERSION.to_managed();
56 let vi1 = ast::view_item {
57 node: ast::view_item_extern_mod(self.sess.ident_of("std"),
62 attr::mk_attr(attr::mk_name_value_item_str(@"vers", version))
68 let vis = vec::append(~[vi1], crate.module.view_items);
69 let mut new_module = ast::_mod {
71 ..crate.module.clone()
74 if !no_prelude(crate.attrs) {
75 // only add `use std::prelude::*;` if there wasn't a
76 // `#[no_implicit_prelude];` at the crate level.
77 new_module = self.fold_mod(&new_module);
80 // FIXME #2543: Bad copy.
87 fn fold_item(&self, item: @ast::item) -> Option<@ast::item> {
88 if !no_prelude(item.attrs) {
89 // only recur if there wasn't `#[no_implicit_prelude];`
90 // on this item, i.e. this means that the prelude is not
91 // implicitly imported though the whole subtree
92 fold::noop_fold_item(item, self)
98 fn fold_mod(&self, module: &ast::_mod) -> ast::_mod {
99 let prelude_path = ast::Path {
104 identifier: self.sess.ident_of("std"),
106 types: opt_vec::Empty,
109 identifier: self.sess.ident_of("prelude"),
111 types: opt_vec::Empty,
116 let vp = @spanned(ast::view_path_glob(prelude_path,
117 ast::DUMMY_NODE_ID));
118 let vi2 = ast::view_item {
119 node: ast::view_item_use(~[vp]),
125 let vis = vec::append(~[vi2], module.view_items);
127 // FIXME #2543: Bad copy.
128 let new_module = ast::_mod {
132 fold::noop_fold_mod(&new_module, self)
136 fn inject_libstd_ref(sess: Session, crate: &ast::Crate) -> @ast::Crate {
137 let fold = StandardLibraryInjector {
140 @fold.fold_crate(crate)