src/libsyntax/ext/build.rs

   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.
   4 //
   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.
  10
  11 use abi;
  12 use ast::{Ident, Generics, Expr};
  13 use ast;
  14 use attr;
  15 use codemap::{Span, respan, Spanned, DUMMY_SP, Pos};
  16 use ext::base::ExtCtxt;
  17 use owned_slice::OwnedSlice;
  18 use parse::token::special_idents;
  19 use parse::token::InternedString;
  20 use parse::token;
  21 use ptr::P;
  22
  23 // Transitional reexports so qquote can find the paths it is looking for
  24 mod syntax {
  25     pub use ext;
  26     pub use parse;
  27 }
  28
  29 pub trait AstBuilder {
  30     // paths
  31     fn path(&self, span: Span, strs: Vec<ast::Ident> ) -> ast::Path;
  32     fn path_ident(&self, span: Span, id: ast::Ident) -> ast::Path;
  33     fn path_global(&self, span: Span, strs: Vec<ast::Ident> ) -> ast::Path;
  34     fn path_all(&self, sp: Span,
  35                 global: bool,
  36                 idents: Vec<ast::Ident> ,
  37                 lifetimes: Vec<ast::Lifetime>,
  38                 types: Vec<P<ast::Ty>>,
  39                 bindings: Vec<P<ast::TypeBinding>> )
  40         -> ast::Path;
  41
  42     fn qpath(&self, self_type: P<ast::Ty>,
  43              trait_path: ast::Path,
  44              ident: ast::Ident)
  45              -> (ast::QSelf, ast::Path);
  46     fn qpath_all(&self, self_type: P<ast::Ty>,
  47                 trait_path: ast::Path,
  48                 ident: ast::Ident,
  49                 lifetimes: Vec<ast::Lifetime>,
  50                 types: Vec<P<ast::Ty>>,
  51                 bindings: Vec<P<ast::TypeBinding>>)
  52                 -> (ast::QSelf, ast::Path);
  53
  54     // types
  55     fn ty_mt(&self, ty: P<ast::Ty>, mutbl: ast::Mutability) -> ast::MutTy;
  56
  57     fn ty(&self, span: Span, ty: ast::Ty_) -> P<ast::Ty>;
  58     fn ty_path(&self, ast::Path) -> P<ast::Ty>;
  59     fn ty_sum(&self, ast::Path, OwnedSlice<ast::TyParamBound>) -> P<ast::Ty>;
  60     fn ty_ident(&self, span: Span, idents: ast::Ident) -> P<ast::Ty>;
  61
  62     fn ty_rptr(&self, span: Span,
  63                ty: P<ast::Ty>,
  64                lifetime: Option<ast::Lifetime>,
  65                mutbl: ast::Mutability) -> P<ast::Ty>;
  66     fn ty_ptr(&self, span: Span,
  67               ty: P<ast::Ty>,
  68               mutbl: ast::Mutability) -> P<ast::Ty>;
  69
  70     fn ty_option(&self, ty: P<ast::Ty>) -> P<ast::Ty>;
  71     fn ty_infer(&self, sp: Span) -> P<ast::Ty>;
  72
  73     fn ty_vars(&self, ty_params: &OwnedSlice<ast::TyParam>) -> Vec<P<ast::Ty>> ;
  74     fn ty_vars_global(&self, ty_params: &OwnedSlice<ast::TyParam>) -> Vec<P<ast::Ty>> ;
  75
  76     fn typaram(&self,
  77                span: Span,
  78                id: ast::Ident,
  79                bounds: OwnedSlice<ast::TyParamBound>,
  80                default: Option<P<ast::Ty>>) -> ast::TyParam;
  81
  82     fn trait_ref(&self, path: ast::Path) -> ast::TraitRef;
  83     fn poly_trait_ref(&self, span: Span, path: ast::Path) -> ast::PolyTraitRef;
  84     fn typarambound(&self, path: ast::Path) -> ast::TyParamBound;
  85     fn lifetime(&self, span: Span, ident: ast::Name) -> ast::Lifetime;
  86     fn lifetime_def(&self,
  87                     span: Span,
  88                     name: ast::Name,
  89                     bounds: Vec<ast::Lifetime>)
  90                     -> ast::LifetimeDef;
  91
  92     // statements
  93     fn stmt_expr(&self, expr: P<ast::Expr>) -> P<ast::Stmt>;
  94     fn stmt_let(&self, sp: Span, mutbl: bool, ident: ast::Ident, ex: P<ast::Expr>) -> P<ast::Stmt>;
  95     fn stmt_let_typed(&self,
  96                       sp: Span,
  97                       mutbl: bool,
  98                       ident: ast::Ident,
  99                       typ: P<ast::Ty>,
 100                       ex: P<ast::Expr>)
 101                       -> P<ast::Stmt>;
 102     fn stmt_item(&self, sp: Span, item: P<ast::Item>) -> P<ast::Stmt>;
 103
 104     // blocks
 105     fn block(&self, span: Span, stmts: Vec<P<ast::Stmt>>,
 106              expr: Option<P<ast::Expr>>) -> P<ast::Block>;
 107     fn block_expr(&self, expr: P<ast::Expr>) -> P<ast::Block>;
 108     fn block_all(&self, span: Span,
 109                  stmts: Vec<P<ast::Stmt>>,
 110                  expr: Option<P<ast::Expr>>) -> P<ast::Block>;
 111
 112     // expressions
 113     fn expr(&self, span: Span, node: ast::Expr_) -> P<ast::Expr>;
 114     fn expr_path(&self, path: ast::Path) -> P<ast::Expr>;
 115     fn expr_qpath(&self, span: Span, qself: ast::QSelf, path: ast::Path) -> P<ast::Expr>;
 116     fn expr_ident(&self, span: Span, id: ast::Ident) -> P<ast::Expr>;
 117
 118     fn expr_self(&self, span: Span) -> P<ast::Expr>;
 119     fn expr_binary(&self, sp: Span, op: ast::BinOp_,
 120                    lhs: P<ast::Expr>, rhs: P<ast::Expr>) -> P<ast::Expr>;
 121     fn expr_deref(&self, sp: Span, e: P<ast::Expr>) -> P<ast::Expr>;
 122     fn expr_unary(&self, sp: Span, op: ast::UnOp, e: P<ast::Expr>) -> P<ast::Expr>;
 123
 124     fn expr_addr_of(&self, sp: Span, e: P<ast::Expr>) -> P<ast::Expr>;
 125     fn expr_mut_addr_of(&self, sp: Span, e: P<ast::Expr>) -> P<ast::Expr>;
 126     fn expr_field_access(&self, span: Span, expr: P<ast::Expr>, ident: ast::Ident) -> P<ast::Expr>;
 127     fn expr_tup_field_access(&self, sp: Span, expr: P<ast::Expr>,
 128                              idx: usize) -> P<ast::Expr>;
 129     fn expr_call(&self, span: Span, expr: P<ast::Expr>, args: Vec<P<ast::Expr>>) -> P<ast::Expr>;
 130     fn expr_call_ident(&self, span: Span, id: ast::Ident, args: Vec<P<ast::Expr>>) -> P<ast::Expr>;
 131     fn expr_call_global(&self, sp: Span, fn_path: Vec<ast::Ident>,
 132                         args: Vec<P<ast::Expr>> ) -> P<ast::Expr>;
 133     fn expr_method_call(&self, span: Span,
 134                         expr: P<ast::Expr>, ident: ast::Ident,
 135                         args: Vec<P<ast::Expr>> ) -> P<ast::Expr>;
 136     fn expr_block(&self, b: P<ast::Block>) -> P<ast::Expr>;
 137     fn expr_cast(&self, sp: Span, expr: P<ast::Expr>, ty: P<ast::Ty>) -> P<ast::Expr>;
 138
 139     fn field_imm(&self, span: Span, name: Ident, e: P<ast::Expr>) -> ast::Field;
 140     fn expr_struct(&self, span: Span, path: ast::Path, fields: Vec<ast::Field>) -> P<ast::Expr>;
 141     fn expr_struct_ident(&self, span: Span, id: ast::Ident,
 142                          fields: Vec<ast::Field>) -> P<ast::Expr>;
 143
 144     fn expr_lit(&self, sp: Span, lit: ast::Lit_) -> P<ast::Expr>;
 145
 146     fn expr_usize(&self, span: Span, i: usize) -> P<ast::Expr>;
 147     fn expr_isize(&self, sp: Span, i: isize) -> P<ast::Expr>;
 148     fn expr_u8(&self, sp: Span, u: u8) -> P<ast::Expr>;
 149     fn expr_u32(&self, sp: Span, u: u32) -> P<ast::Expr>;
 150     fn expr_bool(&self, sp: Span, value: bool) -> P<ast::Expr>;
 151
 152     fn expr_vec(&self, sp: Span, exprs: Vec<P<ast::Expr>>) -> P<ast::Expr>;
 153     fn expr_vec_ng(&self, sp: Span) -> P<ast::Expr>;
 154     fn expr_vec_slice(&self, sp: Span, exprs: Vec<P<ast::Expr>>) -> P<ast::Expr>;
 155     fn expr_str(&self, sp: Span, s: InternedString) -> P<ast::Expr>;
 156
 157     fn expr_some(&self, sp: Span, expr: P<ast::Expr>) -> P<ast::Expr>;
 158     fn expr_none(&self, sp: Span) -> P<ast::Expr>;
 159
 160     fn expr_break(&self, sp: Span) -> P<ast::Expr>;
 161
 162     fn expr_tuple(&self, sp: Span, exprs: Vec<P<ast::Expr>>) -> P<ast::Expr>;
 163
 164     fn expr_fail(&self, span: Span, msg: InternedString) -> P<ast::Expr>;
 165     fn expr_unreachable(&self, span: Span) -> P<ast::Expr>;
 166
 167     fn expr_ok(&self, span: Span, expr: P<ast::Expr>) -> P<ast::Expr>;
 168     fn expr_err(&self, span: Span, expr: P<ast::Expr>) -> P<ast::Expr>;
 169     fn expr_try(&self, span: Span, head: P<ast::Expr>) -> P<ast::Expr>;
 170
 171     fn pat(&self, span: Span, pat: ast::Pat_) -> P<ast::Pat>;
 172     fn pat_wild(&self, span: Span) -> P<ast::Pat>;
 173     fn pat_lit(&self, span: Span, expr: P<ast::Expr>) -> P<ast::Pat>;
 174     fn pat_ident(&self, span: Span, ident: ast::Ident) -> P<ast::Pat>;
 175
 176     fn pat_ident_binding_mode(&self,
 177                               span: Span,
 178                               ident: ast::Ident,
 179                               bm: ast::BindingMode) -> P<ast::Pat>;
 180     fn pat_enum(&self, span: Span, path: ast::Path, subpats: Vec<P<ast::Pat>> ) -> P<ast::Pat>;
 181     fn pat_struct(&self, span: Span,
 182                   path: ast::Path, field_pats: Vec<Spanned<ast::FieldPat>> ) -> P<ast::Pat>;
 183     fn pat_tuple(&self, span: Span, pats: Vec<P<ast::Pat>>) -> P<ast::Pat>;
 184
 185     fn pat_some(&self, span: Span, pat: P<ast::Pat>) -> P<ast::Pat>;
 186     fn pat_none(&self, span: Span) -> P<ast::Pat>;
 187
 188     fn pat_ok(&self, span: Span, pat: P<ast::Pat>) -> P<ast::Pat>;
 189     fn pat_err(&self, span: Span, pat: P<ast::Pat>) -> P<ast::Pat>;
 190
 191     fn arm(&self, span: Span, pats: Vec<P<ast::Pat>>, expr: P<ast::Expr>) -> ast::Arm;
 192     fn arm_unreachable(&self, span: Span) -> ast::Arm;
 193
 194     fn expr_match(&self, span: Span, arg: P<ast::Expr>, arms: Vec<ast::Arm> ) -> P<ast::Expr>;
 195     fn expr_if(&self, span: Span,
 196                cond: P<ast::Expr>, then: P<ast::Expr>, els: Option<P<ast::Expr>>) -> P<ast::Expr>;
 197     fn expr_loop(&self, span: Span, block: P<ast::Block>) -> P<ast::Expr>;
 198
 199     fn lambda_fn_decl(&self, span: Span,
 200                       fn_decl: P<ast::FnDecl>, blk: P<ast::Block>) -> P<ast::Expr>;
 201
 202     fn lambda(&self, span: Span, ids: Vec<ast::Ident> , blk: P<ast::Block>) -> P<ast::Expr>;
 203     fn lambda0(&self, span: Span, blk: P<ast::Block>) -> P<ast::Expr>;
 204     fn lambda1(&self, span: Span, blk: P<ast::Block>, ident: ast::Ident) -> P<ast::Expr>;
 205
 206     fn lambda_expr(&self, span: Span, ids: Vec<ast::Ident> , blk: P<ast::Expr>) -> P<ast::Expr>;
 207     fn lambda_expr_0(&self, span: Span, expr: P<ast::Expr>) -> P<ast::Expr>;
 208     fn lambda_expr_1(&self, span: Span, expr: P<ast::Expr>, ident: ast::Ident) -> P<ast::Expr>;
 209
 210     fn lambda_stmts(&self, span: Span, ids: Vec<ast::Ident>,
 211                     blk: Vec<P<ast::Stmt>>) -> P<ast::Expr>;
 212     fn lambda_stmts_0(&self, span: Span, stmts: Vec<P<ast::Stmt>>) -> P<ast::Expr>;
 213     fn lambda_stmts_1(&self, span: Span, stmts: Vec<P<ast::Stmt>>,
 214                       ident: ast::Ident) -> P<ast::Expr>;
 215
 216     // items
 217     fn item(&self, span: Span,
 218             name: Ident, attrs: Vec<ast::Attribute> , node: ast::Item_) -> P<ast::Item>;
 219
 220     fn arg(&self, span: Span, name: Ident, ty: P<ast::Ty>) -> ast::Arg;
 221     // FIXME unused self
 222     fn fn_decl(&self, inputs: Vec<ast::Arg> , output: P<ast::Ty>) -> P<ast::FnDecl>;
 223
 224     fn item_fn_poly(&self,
 225                     span: Span,
 226                     name: Ident,
 227                     inputs: Vec<ast::Arg> ,
 228                     output: P<ast::Ty>,
 229                     generics: Generics,
 230                     body: P<ast::Block>) -> P<ast::Item>;
 231     fn item_fn(&self,
 232                span: Span,
 233                name: Ident,
 234                inputs: Vec<ast::Arg> ,
 235                output: P<ast::Ty>,
 236                body: P<ast::Block>) -> P<ast::Item>;
 237
 238     fn variant(&self, span: Span, name: Ident, tys: Vec<P<ast::Ty>> ) -> ast::Variant;
 239     fn item_enum_poly(&self,
 240                       span: Span,
 241                       name: Ident,
 242                       enum_definition: ast::EnumDef,
 243                       generics: Generics) -> P<ast::Item>;
 244     fn item_enum(&self, span: Span, name: Ident, enum_def: ast::EnumDef) -> P<ast::Item>;
 245
 246     fn item_struct_poly(&self,
 247                         span: Span,
 248                         name: Ident,
 249                         struct_def: ast::VariantData,
 250                         generics: Generics) -> P<ast::Item>;
 251     fn item_struct(&self, span: Span, name: Ident, struct_def: ast::VariantData) -> P<ast::Item>;
 252
 253     fn item_mod(&self, span: Span, inner_span: Span,
 254                 name: Ident, attrs: Vec<ast::Attribute>,
 255                 items: Vec<P<ast::Item>>) -> P<ast::Item>;
 256
 257     fn item_static(&self,
 258                    span: Span,
 259                    name: Ident,
 260                    ty: P<ast::Ty>,
 261                    mutbl: ast::Mutability,
 262                    expr: P<ast::Expr>)
 263                    -> P<ast::Item>;
 264
 265     fn item_const(&self,
 266                    span: Span,
 267                    name: Ident,
 268                    ty: P<ast::Ty>,
 269                    expr: P<ast::Expr>)
 270                    -> P<ast::Item>;
 271
 272     fn item_ty_poly(&self,
 273                     span: Span,
 274                     name: Ident,
 275                     ty: P<ast::Ty>,
 276                     generics: Generics) -> P<ast::Item>;
 277     fn item_ty(&self, span: Span, name: Ident, ty: P<ast::Ty>) -> P<ast::Item>;
 278
 279     fn attribute(&self, sp: Span, mi: P<ast::MetaItem>) -> ast::Attribute;
 280
 281     fn meta_word(&self, sp: Span, w: InternedString) -> P<ast::MetaItem>;
 282     fn meta_list(&self,
 283                  sp: Span,
 284                  name: InternedString,
 285                  mis: Vec<P<ast::MetaItem>> )
 286                  -> P<ast::MetaItem>;
 287     fn meta_name_value(&self,
 288                        sp: Span,
 289                        name: InternedString,
 290                        value: ast::Lit_)
 291                        -> P<ast::MetaItem>;
 292
 293     fn item_use(&self, sp: Span,
 294                 vis: ast::Visibility, vp: P<ast::ViewPath>) -> P<ast::Item>;
 295     fn item_use_simple(&self, sp: Span, vis: ast::Visibility, path: ast::Path) -> P<ast::Item>;
 296     fn item_use_simple_(&self, sp: Span, vis: ast::Visibility,
 297                         ident: ast::Ident, path: ast::Path) -> P<ast::Item>;
 298     fn item_use_list(&self, sp: Span, vis: ast::Visibility,
 299                      path: Vec<ast::Ident>, imports: &[ast::Ident]) -> P<ast::Item>;
 300     fn item_use_glob(&self, sp: Span,
 301                      vis: ast::Visibility, path: Vec<ast::Ident>) -> P<ast::Item>;
 302 }
 303
 304 impl<'a> AstBuilder for ExtCtxt<'a> {
 305     fn path(&self, span: Span, strs: Vec<ast::Ident> ) -> ast::Path {
 306         self.path_all(span, false, strs, Vec::new(), Vec::new(), Vec::new())
 307     }
 308     fn path_ident(&self, span: Span, id: ast::Ident) -> ast::Path {
 309         self.path(span, vec!(id))
 310     }
 311     fn path_global(&self, span: Span, strs: Vec<ast::Ident> ) -> ast::Path {
 312         self.path_all(span, true, strs, Vec::new(), Vec::new(), Vec::new())
 313     }
 314     fn path_all(&self,
 315                 sp: Span,
 316                 global: bool,
 317                 mut idents: Vec<ast::Ident> ,
 318                 lifetimes: Vec<ast::Lifetime>,
 319                 types: Vec<P<ast::Ty>>,
 320                 bindings: Vec<P<ast::TypeBinding>> )
 321                 -> ast::Path {
 322         let last_identifier = idents.pop().unwrap();
 323         let mut segments: Vec<ast::PathSegment> = idents.into_iter()
 324                                                       .map(|ident| {
 325             ast::PathSegment {
 326                 identifier: ident,
 327                 parameters: ast::PathParameters::none(),
 328             }
 329         }).collect();
 330         segments.push(ast::PathSegment {
 331             identifier: last_identifier,
 332             parameters: ast::AngleBracketedParameters(ast::AngleBracketedParameterData {
 333                 lifetimes: lifetimes,
 334                 types: OwnedSlice::from_vec(types),
 335                 bindings: OwnedSlice::from_vec(bindings),
 336             })
 337         });
 338         ast::Path {
 339             span: sp,
 340             global: global,
 341             segments: segments,
 342         }
 343     }
 344
 345     /// Constructs a qualified path.
 346     ///
 347     /// Constructs a path like `<self_type as trait_path>::ident`.
 348     fn qpath(&self,
 349              self_type: P<ast::Ty>,
 350              trait_path: ast::Path,
 351              ident: ast::Ident)
 352              -> (ast::QSelf, ast::Path) {
 353         self.qpath_all(self_type, trait_path, ident, vec![], vec![], vec![])
 354     }
 355
 356     /// Constructs a qualified path.
 357     ///
 358     /// Constructs a path like `<self_type as trait_path>::ident<'a, T, A=Bar>`.
 359     fn qpath_all(&self,
 360                  self_type: P<ast::Ty>,
 361                  trait_path: ast::Path,
 362                  ident: ast::Ident,
 363                  lifetimes: Vec<ast::Lifetime>,
 364                  types: Vec<P<ast::Ty>>,
 365                  bindings: Vec<P<ast::TypeBinding>>)
 366                  -> (ast::QSelf, ast::Path) {
 367         let mut path = trait_path;
 368         path.segments.push(ast::PathSegment {
 369             identifier: ident,
 370             parameters: ast::AngleBracketedParameters(ast::AngleBracketedParameterData {
 371                 lifetimes: lifetimes,
 372                 types: OwnedSlice::from_vec(types),
 373                 bindings: OwnedSlice::from_vec(bindings),
 374             })
 375         });
 376
 377         (ast::QSelf {
 378             ty: self_type,
 379             position: path.segments.len() - 1
 380         }, path)
 381     }
 382
 383     fn ty_mt(&self, ty: P<ast::Ty>, mutbl: ast::Mutability) -> ast::MutTy {
 384         ast::MutTy {
 385             ty: ty,
 386             mutbl: mutbl
 387         }
 388     }
 389
 390     fn ty(&self, span: Span, ty: ast::Ty_) -> P<ast::Ty> {
 391         P(ast::Ty {
 392             id: ast::DUMMY_NODE_ID,
 393             span: span,
 394             node: ty
 395         })
 396     }
 397
 398     fn ty_path(&self, path: ast::Path) -> P<ast::Ty> {
 399         self.ty(path.span, ast::TyPath(None, path))
 400     }
 401
 402     fn ty_sum(&self, path: ast::Path, bounds: OwnedSlice<ast::TyParamBound>) -> P<ast::Ty> {
 403         self.ty(path.span,
 404                 ast::TyObjectSum(self.ty_path(path),
 405                                  bounds))
 406     }
 407
 408     // Might need to take bounds as an argument in the future, if you ever want
 409     // to generate a bounded existential trait type.
 410     fn ty_ident(&self, span: Span, ident: ast::Ident)
 411         -> P<ast::Ty> {
 412         self.ty_path(self.path_ident(span, ident))
 413     }
 414
 415     fn ty_rptr(&self,
 416                span: Span,
 417                ty: P<ast::Ty>,
 418                lifetime: Option<ast::Lifetime>,
 419                mutbl: ast::Mutability)
 420         -> P<ast::Ty> {
 421         self.ty(span,
 422                 ast::TyRptr(lifetime, self.ty_mt(ty, mutbl)))
 423     }
 424
 425     fn ty_ptr(&self,
 426               span: Span,
 427               ty: P<ast::Ty>,
 428               mutbl: ast::Mutability)
 429         -> P<ast::Ty> {
 430         self.ty(span,
 431                 ast::TyPtr(self.ty_mt(ty, mutbl)))
 432     }
 433
 434     fn ty_option(&self, ty: P<ast::Ty>) -> P<ast::Ty> {
 435         self.ty_path(
 436             self.path_all(DUMMY_SP,
 437                           true,
 438                           self.std_path(&["option", "Option"]),
 439                           Vec::new(),
 440                           vec!( ty ),
 441                           Vec::new()))
 442     }
 443
 444     fn ty_infer(&self, span: Span) -> P<ast::Ty> {
 445         self.ty(span, ast::TyInfer)
 446     }
 447
 448     fn typaram(&self,
 449                span: Span,
 450                id: ast::Ident,
 451                bounds: OwnedSlice<ast::TyParamBound>,
 452                default: Option<P<ast::Ty>>) -> ast::TyParam {
 453         ast::TyParam {
 454             ident: id,
 455             id: ast::DUMMY_NODE_ID,
 456             bounds: bounds,
 457             default: default,
 458             span: span
 459         }
 460     }
 461
 462     // these are strange, and probably shouldn't be used outside of
 463     // pipes. Specifically, the global version possible generates
 464     // incorrect code.
 465     fn ty_vars(&self, ty_params: &OwnedSlice<ast::TyParam>) -> Vec<P<ast::Ty>> {
 466         ty_params.iter().map(|p| self.ty_ident(DUMMY_SP, p.ident)).collect()
 467     }
 468
 469     fn ty_vars_global(&self, ty_params: &OwnedSlice<ast::TyParam>) -> Vec<P<ast::Ty>> {
 470         ty_params
 471             .iter()
 472             .map(|p| self.ty_path(self.path_global(DUMMY_SP, vec!(p.ident))))
 473             .collect()
 474     }
 475
 476     fn trait_ref(&self, path: ast::Path) -> ast::TraitRef {
 477         ast::TraitRef {
 478             path: path,
 479             ref_id: ast::DUMMY_NODE_ID,
 480         }
 481     }
 482
 483     fn poly_trait_ref(&self, span: Span, path: ast::Path) -> ast::PolyTraitRef {
 484         ast::PolyTraitRef {
 485             bound_lifetimes: Vec::new(),
 486             trait_ref: self.trait_ref(path),
 487             span: span,
 488         }
 489     }
 490
 491     fn typarambound(&self, path: ast::Path) -> ast::TyParamBound {
 492         ast::TraitTyParamBound(self.poly_trait_ref(path.span, path), ast::TraitBoundModifier::None)
 493     }
 494
 495     fn lifetime(&self, span: Span, name: ast::Name) -> ast::Lifetime {
 496         ast::Lifetime { id: ast::DUMMY_NODE_ID, span: span, name: name }
 497     }
 498
 499     fn lifetime_def(&self,
 500                     span: Span,
 501                     name: ast::Name,
 502                     bounds: Vec<ast::Lifetime>)
 503                     -> ast::LifetimeDef {
 504         ast::LifetimeDef {
 505             lifetime: self.lifetime(span, name),
 506             bounds: bounds
 507         }
 508     }
 509
 510     fn stmt_expr(&self, expr: P<ast::Expr>) -> P<ast::Stmt> {
 511         P(respan(expr.span, ast::StmtSemi(expr, ast::DUMMY_NODE_ID)))
 512     }
 513
 514     fn stmt_let(&self, sp: Span, mutbl: bool, ident: ast::Ident,
 515                 ex: P<ast::Expr>) -> P<ast::Stmt> {
 516         let pat = if mutbl {
 517             self.pat_ident_binding_mode(sp, ident, ast::BindByValue(ast::MutMutable))
 518         } else {
 519             self.pat_ident(sp, ident)
 520         };
 521         let local = P(ast::Local {
 522             pat: pat,
 523             ty: None,
 524             init: Some(ex),
 525             id: ast::DUMMY_NODE_ID,
 526             span: sp,
 527             attrs: None,
 528         });
 529         let decl = respan(sp, ast::DeclLocal(local));
 530         P(respan(sp, ast::StmtDecl(P(decl), ast::DUMMY_NODE_ID)))
 531     }
 532
 533     fn stmt_let_typed(&self,
 534                       sp: Span,
 535                       mutbl: bool,
 536                       ident: ast::Ident,
 537                       typ: P<ast::Ty>,
 538                       ex: P<ast::Expr>)
 539                       -> P<ast::Stmt> {
 540         let pat = if mutbl {
 541             self.pat_ident_binding_mode(sp, ident, ast::BindByValue(ast::MutMutable))
 542         } else {
 543             self.pat_ident(sp, ident)
 544         };
 545         let local = P(ast::Local {
 546             pat: pat,
 547             ty: Some(typ),
 548             init: Some(ex),
 549             id: ast::DUMMY_NODE_ID,
 550             span: sp,
 551             attrs: None,
 552         });
 553         let decl = respan(sp, ast::DeclLocal(local));
 554         P(respan(sp, ast::StmtDecl(P(decl), ast::DUMMY_NODE_ID)))
 555     }
 556
 557     fn block(&self, span: Span, stmts: Vec<P<ast::Stmt>>,
 558              expr: Option<P<Expr>>) -> P<ast::Block> {
 559         self.block_all(span, stmts, expr)
 560     }
 561
 562     fn stmt_item(&self, sp: Span, item: P<ast::Item>) -> P<ast::Stmt> {
 563         let decl = respan(sp, ast::DeclItem(item));
 564         P(respan(sp, ast::StmtDecl(P(decl), ast::DUMMY_NODE_ID)))
 565     }
 566
 567     fn block_expr(&self, expr: P<ast::Expr>) -> P<ast::Block> {
 568         self.block_all(expr.span, Vec::new(), Some(expr))
 569     }
 570     fn block_all(&self,
 571                  span: Span,
 572                  stmts: Vec<P<ast::Stmt>>,
 573                  expr: Option<P<ast::Expr>>) -> P<ast::Block> {
 574             P(ast::Block {
 575                stmts: stmts,
 576                expr: expr,
 577                id: ast::DUMMY_NODE_ID,
 578                rules: ast::DefaultBlock,
 579                span: span,
 580             })
 581     }
 582
 583     fn expr(&self, span: Span, node: ast::Expr_) -> P<ast::Expr> {
 584         P(ast::Expr {
 585             id: ast::DUMMY_NODE_ID,
 586             node: node,
 587             span: span,
 588             attrs: None,
 589         })
 590     }
 591
 592     fn expr_path(&self, path: ast::Path) -> P<ast::Expr> {
 593         self.expr(path.span, ast::ExprPath(None, path))
 594     }
 595
 596     /// Constructs a QPath expression.
 597     fn expr_qpath(&self, span: Span, qself: ast::QSelf, path: ast::Path) -> P<ast::Expr> {
 598         self.expr(span, ast::ExprPath(Some(qself), path))
 599     }
 600
 601     fn expr_ident(&self, span: Span, id: ast::Ident) -> P<ast::Expr> {
 602         self.expr_path(self.path_ident(span, id))
 603     }
 604     fn expr_self(&self, span: Span) -> P<ast::Expr> {
 605         self.expr_ident(span, special_idents::self_)
 606     }
 607
 608     fn expr_binary(&self, sp: Span, op: ast::BinOp_,
 609                    lhs: P<ast::Expr>, rhs: P<ast::Expr>) -> P<ast::Expr> {
 610         self.expr(sp, ast::ExprBinary(Spanned { node: op, span: sp }, lhs, rhs))
 611     }
 612
 613     fn expr_deref(&self, sp: Span, e: P<ast::Expr>) -> P<ast::Expr> {
 614         self.expr_unary(sp, ast::UnDeref, e)
 615     }
 616     fn expr_unary(&self, sp: Span, op: ast::UnOp, e: P<ast::Expr>) -> P<ast::Expr> {
 617         self.expr(sp, ast::ExprUnary(op, e))
 618     }
 619
 620     fn expr_field_access(&self, sp: Span, expr: P<ast::Expr>, ident: ast::Ident) -> P<ast::Expr> {
 621         let field_span = Span {
 622             lo: sp.lo - Pos::from_usize(ident.name.as_str().len()),
 623             hi: sp.hi,
 624             expn_id: sp.expn_id,
 625         };
 626
 627         let id = Spanned { node: ident, span: field_span };
 628         self.expr(sp, ast::ExprField(expr, id))
 629     }
 630     fn expr_tup_field_access(&self, sp: Span, expr: P<ast::Expr>, idx: usize) -> P<ast::Expr> {
 631         let field_span = Span {
 632             lo: sp.lo - Pos::from_usize(idx.to_string().len()),
 633             hi: sp.hi,
 634             expn_id: sp.expn_id,
 635         };
 636
 637         let id = Spanned { node: idx, span: field_span };
 638         self.expr(sp, ast::ExprTupField(expr, id))
 639     }
 640     fn expr_addr_of(&self, sp: Span, e: P<ast::Expr>) -> P<ast::Expr> {
 641         self.expr(sp, ast::ExprAddrOf(ast::MutImmutable, e))
 642     }
 643     fn expr_mut_addr_of(&self, sp: Span, e: P<ast::Expr>) -> P<ast::Expr> {
 644         self.expr(sp, ast::ExprAddrOf(ast::MutMutable, e))
 645     }
 646
 647     fn expr_call(&self, span: Span, expr: P<ast::Expr>, args: Vec<P<ast::Expr>>) -> P<ast::Expr> {
 648         self.expr(span, ast::ExprCall(expr, args))
 649     }
 650     fn expr_call_ident(&self, span: Span, id: ast::Ident,
 651                        args: Vec<P<ast::Expr>>) -> P<ast::Expr> {
 652         self.expr(span, ast::ExprCall(self.expr_ident(span, id), args))
 653     }
 654     fn expr_call_global(&self, sp: Span, fn_path: Vec<ast::Ident> ,
 655                       args: Vec<P<ast::Expr>> ) -> P<ast::Expr> {
 656         let pathexpr = self.expr_path(self.path_global(sp, fn_path));
 657         self.expr_call(sp, pathexpr, args)
 658     }
 659     fn expr_method_call(&self, span: Span,
 660                         expr: P<ast::Expr>,
 661                         ident: ast::Ident,
 662                         mut args: Vec<P<ast::Expr>> ) -> P<ast::Expr> {
 663         let id = Spanned { node: ident, span: span };
 664         args.insert(0, expr);
 665         self.expr(span, ast::ExprMethodCall(id, Vec::new(), args))
 666     }
 667     fn expr_block(&self, b: P<ast::Block>) -> P<ast::Expr> {
 668         self.expr(b.span, ast::ExprBlock(b))
 669     }
 670     fn field_imm(&self, span: Span, name: Ident, e: P<ast::Expr>) -> ast::Field {
 671         ast::Field { ident: respan(span, name), expr: e, span: span }
 672     }
 673     fn expr_struct(&self, span: Span, path: ast::Path, fields: Vec<ast::Field>) -> P<ast::Expr> {
 674         self.expr(span, ast::ExprStruct(path, fields, None))
 675     }
 676     fn expr_struct_ident(&self, span: Span,
 677                          id: ast::Ident, fields: Vec<ast::Field>) -> P<ast::Expr> {
 678         self.expr_struct(span, self.path_ident(span, id), fields)
 679     }
 680
 681     fn expr_lit(&self, sp: Span, lit: ast::Lit_) -> P<ast::Expr> {
 682         self.expr(sp, ast::ExprLit(P(respan(sp, lit))))
 683     }
 684     fn expr_usize(&self, span: Span, i: usize) -> P<ast::Expr> {
 685         self.expr_lit(span, ast::LitInt(i as u64, ast::UnsignedIntLit(ast::TyUs)))
 686     }
 687     fn expr_isize(&self, sp: Span, i: isize) -> P<ast::Expr> {
 688         self.expr_lit(sp, ast::LitInt(i as u64, ast::SignedIntLit(ast::TyIs,
 689                                                                   ast::Sign::new(i))))
 690     }
 691     fn expr_u32(&self, sp: Span, u: u32) -> P<ast::Expr> {
 692         self.expr_lit(sp, ast::LitInt(u as u64, ast::UnsignedIntLit(ast::TyU32)))
 693     }
 694     fn expr_u8(&self, sp: Span, u: u8) -> P<ast::Expr> {
 695         self.expr_lit(sp, ast::LitInt(u as u64, ast::UnsignedIntLit(ast::TyU8)))
 696     }
 697     fn expr_bool(&self, sp: Span, value: bool) -> P<ast::Expr> {
 698         self.expr_lit(sp, ast::LitBool(value))
 699     }
 700
 701     fn expr_vec(&self, sp: Span, exprs: Vec<P<ast::Expr>>) -> P<ast::Expr> {
 702         self.expr(sp, ast::ExprVec(exprs))
 703     }
 704     fn expr_vec_ng(&self, sp: Span) -> P<ast::Expr> {
 705         self.expr_call_global(sp, self.std_path(&["vec", "Vec", "new"]),
 706                               Vec::new())
 707     }
 708     fn expr_vec_slice(&self, sp: Span, exprs: Vec<P<ast::Expr>>) -> P<ast::Expr> {
 709         self.expr_addr_of(sp, self.expr_vec(sp, exprs))
 710     }
 711     fn expr_str(&self, sp: Span, s: InternedString) -> P<ast::Expr> {
 712         self.expr_lit(sp, ast::LitStr(s, ast::CookedStr))
 713     }
 714
 715     fn expr_cast(&self, sp: Span, expr: P<ast::Expr>, ty: P<ast::Ty>) -> P<ast::Expr> {
 716         self.expr(sp, ast::ExprCast(expr, ty))
 717     }
 718
 719
 720     fn expr_some(&self, sp: Span, expr: P<ast::Expr>) -> P<ast::Expr> {
 721         let some = self.std_path(&["option", "Option", "Some"]);
 722         self.expr_call_global(sp, some, vec!(expr))
 723     }
 724
 725     fn expr_none(&self, sp: Span) -> P<ast::Expr> {
 726         let none = self.std_path(&["option", "Option", "None"]);
 727         let none = self.path_global(sp, none);
 728         self.expr_path(none)
 729     }
 730
 731
 732     fn expr_break(&self, sp: Span) -> P<ast::Expr> {
 733         self.expr(sp, ast::ExprBreak(None))
 734     }
 735
 736
 737     fn expr_tuple(&self, sp: Span, exprs: Vec<P<ast::Expr>>) -> P<ast::Expr> {
 738         self.expr(sp, ast::ExprTup(exprs))
 739     }
 740
 741     fn expr_fail(&self, span: Span, msg: InternedString) -> P<ast::Expr> {
 742         let loc = self.codemap().lookup_char_pos(span.lo);
 743         let expr_file = self.expr_str(span,
 744                                       token::intern_and_get_ident(&loc.file.name));
 745         let expr_line = self.expr_u32(span, loc.line as u32);
 746         let expr_file_line_tuple = self.expr_tuple(span, vec!(expr_file, expr_line));
 747         let expr_file_line_ptr = self.expr_addr_of(span, expr_file_line_tuple);
 748         self.expr_call_global(
 749             span,
 750             self.std_path(&["rt", "begin_unwind"]),
 751             vec!(
 752                 self.expr_str(span, msg),
 753                 expr_file_line_ptr))
 754     }
 755
 756     fn expr_unreachable(&self, span: Span) -> P<ast::Expr> {
 757         self.expr_fail(span,
 758                        InternedString::new(
 759                            "internal error: entered unreachable code"))
 760     }
 761
 762     fn expr_ok(&self, sp: Span, expr: P<ast::Expr>) -> P<ast::Expr> {
 763         let ok = self.std_path(&["result", "Result", "Ok"]);
 764         self.expr_call_global(sp, ok, vec!(expr))
 765     }
 766
 767     fn expr_err(&self, sp: Span, expr: P<ast::Expr>) -> P<ast::Expr> {
 768         let err = self.std_path(&["result", "Result", "Err"]);
 769         self.expr_call_global(sp, err, vec!(expr))
 770     }
 771
 772     fn expr_try(&self, sp: Span, head: P<ast::Expr>) -> P<ast::Expr> {
 773         let ok = self.std_path(&["result", "Result", "Ok"]);
 774         let ok_path = self.path_global(sp, ok);
 775         let err = self.std_path(&["result", "Result", "Err"]);
 776         let err_path = self.path_global(sp, err);
 777
 778         let binding_variable = self.ident_of("__try_var");
 779         let binding_pat = self.pat_ident(sp, binding_variable);
 780         let binding_expr = self.expr_ident(sp, binding_variable);
 781
 782         // Ok(__try_var) pattern
 783         let ok_pat = self.pat_enum(sp, ok_path, vec!(binding_pat.clone()));
 784
 785         // Err(__try_var)  (pattern and expression resp.)
 786         let err_pat = self.pat_enum(sp, err_path.clone(), vec!(binding_pat));
 787         let err_inner_expr = self.expr_call(sp, self.expr_path(err_path),
 788                                             vec!(binding_expr.clone()));
 789         // return Err(__try_var)
 790         let err_expr = self.expr(sp, ast::ExprRet(Some(err_inner_expr)));
 791
 792         // Ok(__try_var) => __try_var
 793         let ok_arm = self.arm(sp, vec!(ok_pat), binding_expr);
 794         // Err(__try_var) => return Err(__try_var)
 795         let err_arm = self.arm(sp, vec!(err_pat), err_expr);
 796
 797         // match head { Ok() => ..., Err() => ... }
 798         self.expr_match(sp, head, vec!(ok_arm, err_arm))
 799     }
 800
 801
 802     fn pat(&self, span: Span, pat: ast::Pat_) -> P<ast::Pat> {
 803         P(ast::Pat { id: ast::DUMMY_NODE_ID, node: pat, span: span })
 804     }
 805     fn pat_wild(&self, span: Span) -> P<ast::Pat> {
 806         self.pat(span, ast::PatWild)
 807     }
 808     fn pat_lit(&self, span: Span, expr: P<ast::Expr>) -> P<ast::Pat> {
 809         self.pat(span, ast::PatLit(expr))
 810     }
 811     fn pat_ident(&self, span: Span, ident: ast::Ident) -> P<ast::Pat> {
 812         self.pat_ident_binding_mode(span, ident, ast::BindByValue(ast::MutImmutable))
 813     }
 814
 815     fn pat_ident_binding_mode(&self,
 816                               span: Span,
 817                               ident: ast::Ident,
 818                               bm: ast::BindingMode) -> P<ast::Pat> {
 819         let pat = ast::PatIdent(bm, Spanned{span: span, node: ident}, None);
 820         self.pat(span, pat)
 821     }
 822     fn pat_enum(&self, span: Span, path: ast::Path, subpats: Vec<P<ast::Pat>>) -> P<ast::Pat> {
 823         let pat = ast::PatEnum(path, Some(subpats));
 824         self.pat(span, pat)
 825     }
 826     fn pat_struct(&self, span: Span,
 827                   path: ast::Path, field_pats: Vec<Spanned<ast::FieldPat>>) -> P<ast::Pat> {
 828         let pat = ast::PatStruct(path, field_pats, false);
 829         self.pat(span, pat)
 830     }
 831     fn pat_tuple(&self, span: Span, pats: Vec<P<ast::Pat>>) -> P<ast::Pat> {
 832         self.pat(span, ast::PatTup(pats))
 833     }
 834
 835     fn pat_some(&self, span: Span, pat: P<ast::Pat>) -> P<ast::Pat> {
 836         let some = self.std_path(&["option", "Option", "Some"]);
 837         let path = self.path_global(span, some);
 838         self.pat_enum(span, path, vec!(pat))
 839     }
 840
 841     fn pat_none(&self, span: Span) -> P<ast::Pat> {
 842         let some = self.std_path(&["option", "Option", "None"]);
 843         let path = self.path_global(span, some);
 844         self.pat_enum(span, path, vec!())
 845     }
 846
 847     fn pat_ok(&self, span: Span, pat: P<ast::Pat>) -> P<ast::Pat> {
 848         let some = self.std_path(&["result", "Result", "Ok"]);
 849         let path = self.path_global(span, some);
 850         self.pat_enum(span, path, vec!(pat))
 851     }
 852
 853     fn pat_err(&self, span: Span, pat: P<ast::Pat>) -> P<ast::Pat> {
 854         let some = self.std_path(&["result", "Result", "Err"]);
 855         let path = self.path_global(span, some);
 856         self.pat_enum(span, path, vec!(pat))
 857     }
 858
 859     fn arm(&self, _span: Span, pats: Vec<P<ast::Pat>>, expr: P<ast::Expr>) -> ast::Arm {
 860         ast::Arm {
 861             attrs: vec!(),
 862             pats: pats,
 863             guard: None,
 864             body: expr
 865         }
 866     }
 867
 868     fn arm_unreachable(&self, span: Span) -> ast::Arm {
 869         self.arm(span, vec!(self.pat_wild(span)), self.expr_unreachable(span))
 870     }
 871
 872     fn expr_match(&self, span: Span, arg: P<ast::Expr>, arms: Vec<ast::Arm>) -> P<Expr> {
 873         self.expr(span, ast::ExprMatch(arg, arms))
 874     }
 875
 876     fn expr_if(&self, span: Span, cond: P<ast::Expr>,
 877                then: P<ast::Expr>, els: Option<P<ast::Expr>>) -> P<ast::Expr> {
 878         let els = els.map(|x| self.expr_block(self.block_expr(x)));
 879         self.expr(span, ast::ExprIf(cond, self.block_expr(then), els))
 880     }
 881
 882     fn expr_loop(&self, span: Span, block: P<ast::Block>) -> P<ast::Expr> {
 883         self.expr(span, ast::ExprLoop(block, None))
 884     }
 885
 886     fn lambda_fn_decl(&self, span: Span,
 887                       fn_decl: P<ast::FnDecl>, blk: P<ast::Block>) -> P<ast::Expr> {
 888         self.expr(span, ast::ExprClosure(ast::CaptureByRef, fn_decl, blk))
 889     }
 890     fn lambda(&self, span: Span, ids: Vec<ast::Ident>, blk: P<ast::Block>) -> P<ast::Expr> {
 891         let fn_decl = self.fn_decl(
 892             ids.iter().map(|id| self.arg(span, *id, self.ty_infer(span))).collect(),
 893             self.ty_infer(span));
 894
 895         self.expr(span, ast::ExprClosure(ast::CaptureByRef, fn_decl, blk))
 896     }
 897     fn lambda0(&self, span: Span, blk: P<ast::Block>) -> P<ast::Expr> {
 898         self.lambda(span, Vec::new(), blk)
 899     }
 900
 901     fn lambda1(&self, span: Span, blk: P<ast::Block>, ident: ast::Ident) -> P<ast::Expr> {
 902         self.lambda(span, vec!(ident), blk)
 903     }
 904
 905     fn lambda_expr(&self, span: Span, ids: Vec<ast::Ident>,
 906                    expr: P<ast::Expr>) -> P<ast::Expr> {
 907         self.lambda(span, ids, self.block_expr(expr))
 908     }
 909     fn lambda_expr_0(&self, span: Span, expr: P<ast::Expr>) -> P<ast::Expr> {
 910         self.lambda0(span, self.block_expr(expr))
 911     }
 912     fn lambda_expr_1(&self, span: Span, expr: P<ast::Expr>, ident: ast::Ident) -> P<ast::Expr> {
 913         self.lambda1(span, self.block_expr(expr), ident)
 914     }
 915
 916     fn lambda_stmts(&self,
 917                     span: Span,
 918                     ids: Vec<ast::Ident>,
 919                     stmts: Vec<P<ast::Stmt>>)
 920                     -> P<ast::Expr> {
 921         self.lambda(span, ids, self.block(span, stmts, None))
 922     }
 923     fn lambda_stmts_0(&self, span: Span, stmts: Vec<P<ast::Stmt>>) -> P<ast::Expr> {
 924         self.lambda0(span, self.block(span, stmts, None))
 925     }
 926     fn lambda_stmts_1(&self, span: Span, stmts: Vec<P<ast::Stmt>>,
 927                       ident: ast::Ident) -> P<ast::Expr> {
 928         self.lambda1(span, self.block(span, stmts, None), ident)
 929     }
 930
 931     fn arg(&self, span: Span, ident: ast::Ident, ty: P<ast::Ty>) -> ast::Arg {
 932         let arg_pat = self.pat_ident(span, ident);
 933         ast::Arg {
 934             ty: ty,
 935             pat: arg_pat,
 936             id: ast::DUMMY_NODE_ID
 937         }
 938     }
 939
 940     // FIXME unused self
 941     fn fn_decl(&self, inputs: Vec<ast::Arg>, output: P<ast::Ty>) -> P<ast::FnDecl> {
 942         P(ast::FnDecl {
 943             inputs: inputs,
 944             output: ast::Return(output),
 945             variadic: false
 946         })
 947     }
 948
 949     fn item(&self, span: Span, name: Ident,
 950             attrs: Vec<ast::Attribute>, node: ast::Item_) -> P<ast::Item> {
 951         // FIXME: Would be nice if our generated code didn't violate
 952         // Rust coding conventions
 953         P(ast::Item {
 954             ident: name,
 955             attrs: attrs,
 956             id: ast::DUMMY_NODE_ID,
 957             node: node,
 958             vis: ast::Inherited,
 959             span: span
 960         })
 961     }
 962
 963     fn item_fn_poly(&self,
 964                     span: Span,
 965                     name: Ident,
 966                     inputs: Vec<ast::Arg> ,
 967                     output: P<ast::Ty>,
 968                     generics: Generics,
 969                     body: P<ast::Block>) -> P<ast::Item> {
 970         self.item(span,
 971                   name,
 972                   Vec::new(),
 973                   ast::ItemFn(self.fn_decl(inputs, output),
 974                               ast::Unsafety::Normal,
 975                               ast::Constness::NotConst,
 976                               abi::Rust,
 977                               generics,
 978                               body))
 979     }
 980
 981     fn item_fn(&self,
 982                span: Span,
 983                name: Ident,
 984                inputs: Vec<ast::Arg> ,
 985                output: P<ast::Ty>,
 986                body: P<ast::Block>
 987               ) -> P<ast::Item> {
 988         self.item_fn_poly(
 989             span,
 990             name,
 991             inputs,
 992             output,
 993             Generics::default(),
 994             body)
 995     }
 996
 997     fn variant(&self, span: Span, name: Ident, tys: Vec<P<ast::Ty>> ) -> ast::Variant {
 998         let fields: Vec<_> = tys.into_iter().map(|ty| {
 999             Spanned { span: ty.span, node: ast::StructField_ {
1000                 ty: ty,
1001                 kind: ast::UnnamedField(ast::Inherited),
1002                 attrs: Vec::new(),
1003                 id: ast::DUMMY_NODE_ID,
1004             }}
1005         }).collect();
1006
1007         let vdata = if fields.is_empty() {
1008             ast::VariantData::Unit(ast::DUMMY_NODE_ID)
1009         } else {
1010             ast::VariantData::Tuple(fields, ast::DUMMY_NODE_ID)
1011         };
1012
1013         respan(span,
1014                ast::Variant_ {
1015                    name: name,
1016                    attrs: Vec::new(),
1017                    data: vdata,
1018                    disr_expr: None,
1019                })
1020     }
1021
1022     fn item_enum_poly(&self, span: Span, name: Ident,
1023                       enum_definition: ast::EnumDef,
1024                       generics: Generics) -> P<ast::Item> {
1025         self.item(span, name, Vec::new(), ast::ItemEnum(enum_definition, generics))
1026     }
1027
1028     fn item_enum(&self, span: Span, name: Ident,
1029                  enum_definition: ast::EnumDef) -> P<ast::Item> {
1030         self.item_enum_poly(span, name, enum_definition,
1031                             Generics::default())
1032     }
1033
1034     fn item_struct(&self, span: Span, name: Ident,
1035                    struct_def: ast::VariantData) -> P<ast::Item> {
1036         self.item_struct_poly(
1037             span,
1038             name,
1039             struct_def,
1040             Generics::default()
1041         )
1042     }
1043
1044     fn item_struct_poly(&self, span: Span, name: Ident,
1045         struct_def: ast::VariantData, generics: Generics) -> P<ast::Item> {
1046         self.item(span, name, Vec::new(), ast::ItemStruct(struct_def, generics))
1047     }
1048
1049     fn item_mod(&self, span: Span, inner_span: Span, name: Ident,
1050                 attrs: Vec<ast::Attribute>,
1051                 items: Vec<P<ast::Item>>) -> P<ast::Item> {
1052         self.item(
1053             span,
1054             name,
1055             attrs,
1056             ast::ItemMod(ast::Mod {
1057                 inner: inner_span,
1058                 items: items,
1059             })
1060         )
1061     }
1062
1063     fn item_static(&self,
1064                    span: Span,
1065                    name: Ident,
1066                    ty: P<ast::Ty>,
1067                    mutbl: ast::Mutability,
1068                    expr: P<ast::Expr>)
1069                    -> P<ast::Item> {
1070         self.item(span, name, Vec::new(), ast::ItemStatic(ty, mutbl, expr))
1071     }
1072
1073     fn item_const(&self,
1074                   span: Span,
1075                   name: Ident,
1076                   ty: P<ast::Ty>,
1077                   expr: P<ast::Expr>)
1078                   -> P<ast::Item> {
1079         self.item(span, name, Vec::new(), ast::ItemConst(ty, expr))
1080     }
1081
1082     fn item_ty_poly(&self, span: Span, name: Ident, ty: P<ast::Ty>,
1083                     generics: Generics) -> P<ast::Item> {
1084         self.item(span, name, Vec::new(), ast::ItemTy(ty, generics))
1085     }
1086
1087     fn item_ty(&self, span: Span, name: Ident, ty: P<ast::Ty>) -> P<ast::Item> {
1088         self.item_ty_poly(span, name, ty, Generics::default())
1089     }
1090
1091     fn attribute(&self, sp: Span, mi: P<ast::MetaItem>) -> ast::Attribute {
1092         respan(sp, ast::Attribute_ {
1093             id: attr::mk_attr_id(),
1094             style: ast::AttrStyle::Outer,
1095             value: mi,
1096             is_sugared_doc: false,
1097         })
1098     }
1099
1100     fn meta_word(&self, sp: Span, w: InternedString) -> P<ast::MetaItem> {
1101         P(respan(sp, ast::MetaWord(w)))
1102     }
1103     fn meta_list(&self,
1104                  sp: Span,
1105                  name: InternedString,
1106                  mis: Vec<P<ast::MetaItem>> )
1107                  -> P<ast::MetaItem> {
1108         P(respan(sp, ast::MetaList(name, mis)))
1109     }
1110     fn meta_name_value(&self,
1111                        sp: Span,
1112                        name: InternedString,
1113                        value: ast::Lit_)
1114                        -> P<ast::MetaItem> {
1115         P(respan(sp, ast::MetaNameValue(name, respan(sp, value))))
1116     }
1117
1118     fn item_use(&self, sp: Span,
1119                 vis: ast::Visibility, vp: P<ast::ViewPath>) -> P<ast::Item> {
1120         P(ast::Item {
1121             id: ast::DUMMY_NODE_ID,
1122             ident: special_idents::invalid,
1123             attrs: vec![],
1124             node: ast::ItemUse(vp),
1125             vis: vis,
1126             span: sp
1127         })
1128     }
1129
1130     fn item_use_simple(&self, sp: Span, vis: ast::Visibility, path: ast::Path) -> P<ast::Item> {
1131         let last = path.segments.last().unwrap().identifier;
1132         self.item_use_simple_(sp, vis, last, path)
1133     }
1134
1135     fn item_use_simple_(&self, sp: Span, vis: ast::Visibility,
1136                         ident: ast::Ident, path: ast::Path) -> P<ast::Item> {
1137         self.item_use(sp, vis,
1138                       P(respan(sp,
1139                                ast::ViewPathSimple(ident,
1140                                                    path))))
1141     }
1142
1143     fn item_use_list(&self, sp: Span, vis: ast::Visibility,
1144                      path: Vec<ast::Ident>, imports: &[ast::Ident]) -> P<ast::Item> {
1145         let imports = imports.iter().map(|id| {
1146             respan(sp, ast::PathListIdent { name: *id, rename: None, id: ast::DUMMY_NODE_ID })
1147         }).collect();
1148
1149         self.item_use(sp, vis,
1150                       P(respan(sp,
1151                                ast::ViewPathList(self.path(sp, path),
1152                                                  imports))))
1153     }
1154
1155     fn item_use_glob(&self, sp: Span,
1156                      vis: ast::Visibility, path: Vec<ast::Ident>) -> P<ast::Item> {
1157         self.item_use(sp, vis,
1158                       P(respan(sp,
1159                                ast::ViewPathGlob(self.path(sp, path)))))
1160     }
1161 }