src/librustc_expand/build.rs

   1 use crate::base::ExtCtxt;
   2
   3 use rustc_ast::ast::{self, AttrVec, BlockCheckMode, Expr, PatKind, UnOp};
   4 use rustc_ast::attr;
   5 use rustc_ast::ptr::P;
   6 use rustc_span::source_map::{respan, Spanned};
   7 use rustc_span::symbol::{kw, sym, Ident, Symbol};
   8
   9 use rustc_span::Span;
  10
  11 impl<'a> ExtCtxt<'a> {
  12     pub fn path(&self, span: Span, strs: Vec<Ident>) -> ast::Path {
  13         self.path_all(span, false, strs, vec![])
  14     }
  15     pub fn path_ident(&self, span: Span, id: Ident) -> ast::Path {
  16         self.path(span, vec![id])
  17     }
  18     pub fn path_global(&self, span: Span, strs: Vec<Ident>) -> ast::Path {
  19         self.path_all(span, true, strs, vec![])
  20     }
  21     pub fn path_all(
  22         &self,
  23         span: Span,
  24         global: bool,
  25         mut idents: Vec<Ident>,
  26         args: Vec<ast::GenericArg>,
  27     ) -> ast::Path {
  28         assert!(!idents.is_empty());
  29         let add_root = global && !idents[0].is_path_segment_keyword();
  30         let mut segments = Vec::with_capacity(idents.len() + add_root as usize);
  31         if add_root {
  32             segments.push(ast::PathSegment::path_root(span));
  33         }
  34         let last_ident = idents.pop().unwrap();
  35         segments.extend(
  36             idents.into_iter().map(|ident| ast::PathSegment::from_ident(ident.with_span_pos(span))),
  37         );
  38         let args = if !args.is_empty() {
  39             let args = args.into_iter().map(ast::AngleBracketedArg::Arg).collect();
  40             ast::AngleBracketedArgs { args, span }.into()
  41         } else {
  42             None
  43         };
  44         segments.push(ast::PathSegment {
  45             ident: last_ident.with_span_pos(span),
  46             id: ast::DUMMY_NODE_ID,
  47             args,
  48         });
  49         ast::Path { span, segments }
  50     }
  51
  52     pub fn ty_mt(&self, ty: P<ast::Ty>, mutbl: ast::Mutability) -> ast::MutTy {
  53         ast::MutTy { ty, mutbl }
  54     }
  55
  56     pub fn ty(&self, span: Span, kind: ast::TyKind) -> P<ast::Ty> {
  57         P(ast::Ty { id: ast::DUMMY_NODE_ID, span, kind })
  58     }
  59
  60     pub fn ty_path(&self, path: ast::Path) -> P<ast::Ty> {
  61         self.ty(path.span, ast::TyKind::Path(None, path))
  62     }
  63
  64     // Might need to take bounds as an argument in the future, if you ever want
  65     // to generate a bounded existential trait type.
  66     pub fn ty_ident(&self, span: Span, ident: Ident) -> P<ast::Ty> {
  67         self.ty_path(self.path_ident(span, ident))
  68     }
  69
  70     pub fn anon_const(&self, span: Span, kind: ast::ExprKind) -> ast::AnonConst {
  71         ast::AnonConst {
  72             id: ast::DUMMY_NODE_ID,
  73             value: P(ast::Expr {
  74                 id: ast::DUMMY_NODE_ID,
  75                 kind,
  76                 span,
  77                 attrs: AttrVec::new(),
  78                 tokens: None,
  79             }),
  80         }
  81     }
  82
  83     pub fn const_ident(&self, span: Span, ident: Ident) -> ast::AnonConst {
  84         self.anon_const(span, ast::ExprKind::Path(None, self.path_ident(span, ident)))
  85     }
  86
  87     pub fn ty_rptr(
  88         &self,
  89         span: Span,
  90         ty: P<ast::Ty>,
  91         lifetime: Option<ast::Lifetime>,
  92         mutbl: ast::Mutability,
  93     ) -> P<ast::Ty> {
  94         self.ty(span, ast::TyKind::Rptr(lifetime, self.ty_mt(ty, mutbl)))
  95     }
  96
  97     pub fn ty_ptr(&self, span: Span, ty: P<ast::Ty>, mutbl: ast::Mutability) -> P<ast::Ty> {
  98         self.ty(span, ast::TyKind::Ptr(self.ty_mt(ty, mutbl)))
  99     }
 100
 101     pub fn typaram(
 102         &self,
 103         span: Span,
 104         ident: Ident,
 105         attrs: Vec<ast::Attribute>,
 106         bounds: ast::GenericBounds,
 107         default: Option<P<ast::Ty>>,
 108     ) -> ast::GenericParam {
 109         ast::GenericParam {
 110             ident: ident.with_span_pos(span),
 111             id: ast::DUMMY_NODE_ID,
 112             attrs: attrs.into(),
 113             bounds,
 114             kind: ast::GenericParamKind::Type { default },
 115             is_placeholder: false,
 116         }
 117     }
 118
 119     pub fn trait_ref(&self, path: ast::Path) -> ast::TraitRef {
 120         ast::TraitRef { path, ref_id: ast::DUMMY_NODE_ID }
 121     }
 122
 123     pub fn poly_trait_ref(&self, span: Span, path: ast::Path) -> ast::PolyTraitRef {
 124         ast::PolyTraitRef {
 125             bound_generic_params: Vec::new(),
 126             trait_ref: self.trait_ref(path),
 127             span,
 128         }
 129     }
 130
 131     pub fn trait_bound(&self, path: ast::Path) -> ast::GenericBound {
 132         ast::GenericBound::Trait(
 133             self.poly_trait_ref(path.span, path),
 134             ast::TraitBoundModifier::None,
 135         )
 136     }
 137
 138     pub fn lifetime(&self, span: Span, ident: Ident) -> ast::Lifetime {
 139         ast::Lifetime { id: ast::DUMMY_NODE_ID, ident: ident.with_span_pos(span) }
 140     }
 141
 142     pub fn lifetime_def(
 143         &self,
 144         span: Span,
 145         ident: Ident,
 146         attrs: Vec<ast::Attribute>,
 147         bounds: ast::GenericBounds,
 148     ) -> ast::GenericParam {
 149         let lifetime = self.lifetime(span, ident);
 150         ast::GenericParam {
 151             ident: lifetime.ident,
 152             id: lifetime.id,
 153             attrs: attrs.into(),
 154             bounds,
 155             kind: ast::GenericParamKind::Lifetime,
 156             is_placeholder: false,
 157         }
 158     }
 159
 160     pub fn stmt_expr(&self, expr: P<ast::Expr>) -> ast::Stmt {
 161         ast::Stmt { id: ast::DUMMY_NODE_ID, span: expr.span, kind: ast::StmtKind::Expr(expr) }
 162     }
 163
 164     pub fn stmt_let(&self, sp: Span, mutbl: bool, ident: Ident, ex: P<ast::Expr>) -> ast::Stmt {
 165         let pat = if mutbl {
 166             let binding_mode = ast::BindingMode::ByValue(ast::Mutability::Mut);
 167             self.pat_ident_binding_mode(sp, ident, binding_mode)
 168         } else {
 169             self.pat_ident(sp, ident)
 170         };
 171         let local = P(ast::Local {
 172             pat,
 173             ty: None,
 174             init: Some(ex),
 175             id: ast::DUMMY_NODE_ID,
 176             span: sp,
 177             attrs: AttrVec::new(),
 178         });
 179         ast::Stmt { id: ast::DUMMY_NODE_ID, kind: ast::StmtKind::Local(local), span: sp }
 180     }
 181
 182     // Generates `let _: Type;`, which is usually used for type assertions.
 183     pub fn stmt_let_type_only(&self, span: Span, ty: P<ast::Ty>) -> ast::Stmt {
 184         let local = P(ast::Local {
 185             pat: self.pat_wild(span),
 186             ty: Some(ty),
 187             init: None,
 188             id: ast::DUMMY_NODE_ID,
 189             span,
 190             attrs: AttrVec::new(),
 191         });
 192         ast::Stmt { id: ast::DUMMY_NODE_ID, kind: ast::StmtKind::Local(local), span }
 193     }
 194
 195     pub fn stmt_item(&self, sp: Span, item: P<ast::Item>) -> ast::Stmt {
 196         ast::Stmt { id: ast::DUMMY_NODE_ID, kind: ast::StmtKind::Item(item), span: sp }
 197     }
 198
 199     pub fn block_expr(&self, expr: P<ast::Expr>) -> P<ast::Block> {
 200         self.block(
 201             expr.span,
 202             vec![ast::Stmt {
 203                 id: ast::DUMMY_NODE_ID,
 204                 span: expr.span,
 205                 kind: ast::StmtKind::Expr(expr),
 206             }],
 207         )
 208     }
 209     pub fn block(&self, span: Span, stmts: Vec<ast::Stmt>) -> P<ast::Block> {
 210         P(ast::Block { stmts, id: ast::DUMMY_NODE_ID, rules: BlockCheckMode::Default, span })
 211     }
 212
 213     pub fn expr(&self, span: Span, kind: ast::ExprKind) -> P<ast::Expr> {
 214         P(ast::Expr { id: ast::DUMMY_NODE_ID, kind, span, attrs: AttrVec::new(), tokens: None })
 215     }
 216
 217     pub fn expr_path(&self, path: ast::Path) -> P<ast::Expr> {
 218         self.expr(path.span, ast::ExprKind::Path(None, path))
 219     }
 220
 221     pub fn expr_ident(&self, span: Span, id: Ident) -> P<ast::Expr> {
 222         self.expr_path(self.path_ident(span, id))
 223     }
 224     pub fn expr_self(&self, span: Span) -> P<ast::Expr> {
 225         self.expr_ident(span, Ident::with_dummy_span(kw::SelfLower))
 226     }
 227
 228     pub fn expr_binary(
 229         &self,
 230         sp: Span,
 231         op: ast::BinOpKind,
 232         lhs: P<ast::Expr>,
 233         rhs: P<ast::Expr>,
 234     ) -> P<ast::Expr> {
 235         self.expr(sp, ast::ExprKind::Binary(Spanned { node: op, span: sp }, lhs, rhs))
 236     }
 237
 238     pub fn expr_deref(&self, sp: Span, e: P<ast::Expr>) -> P<ast::Expr> {
 239         self.expr(sp, ast::ExprKind::Unary(UnOp::Deref, e))
 240     }
 241
 242     pub fn expr_addr_of(&self, sp: Span, e: P<ast::Expr>) -> P<ast::Expr> {
 243         self.expr(sp, ast::ExprKind::AddrOf(ast::BorrowKind::Ref, ast::Mutability::Not, e))
 244     }
 245
 246     pub fn expr_call(
 247         &self,
 248         span: Span,
 249         expr: P<ast::Expr>,
 250         args: Vec<P<ast::Expr>>,
 251     ) -> P<ast::Expr> {
 252         self.expr(span, ast::ExprKind::Call(expr, args))
 253     }
 254     pub fn expr_call_ident(&self, span: Span, id: Ident, args: Vec<P<ast::Expr>>) -> P<ast::Expr> {
 255         self.expr(span, ast::ExprKind::Call(self.expr_ident(span, id), args))
 256     }
 257     pub fn expr_call_global(
 258         &self,
 259         sp: Span,
 260         fn_path: Vec<Ident>,
 261         args: Vec<P<ast::Expr>>,
 262     ) -> P<ast::Expr> {
 263         let pathexpr = self.expr_path(self.path_global(sp, fn_path));
 264         self.expr_call(sp, pathexpr, args)
 265     }
 266     pub fn expr_method_call(
 267         &self,
 268         span: Span,
 269         expr: P<ast::Expr>,
 270         ident: Ident,
 271         mut args: Vec<P<ast::Expr>>,
 272     ) -> P<ast::Expr> {
 273         args.insert(0, expr);
 274         let segment = ast::PathSegment::from_ident(ident.with_span_pos(span));
 275         self.expr(span, ast::ExprKind::MethodCall(segment, args, span))
 276     }
 277     pub fn expr_block(&self, b: P<ast::Block>) -> P<ast::Expr> {
 278         self.expr(b.span, ast::ExprKind::Block(b, None))
 279     }
 280     pub fn field_imm(&self, span: Span, ident: Ident, e: P<ast::Expr>) -> ast::Field {
 281         ast::Field {
 282             ident: ident.with_span_pos(span),
 283             expr: e,
 284             span,
 285             is_shorthand: false,
 286             attrs: AttrVec::new(),
 287             id: ast::DUMMY_NODE_ID,
 288             is_placeholder: false,
 289         }
 290     }
 291     pub fn expr_struct(
 292         &self,
 293         span: Span,
 294         path: ast::Path,
 295         fields: Vec<ast::Field>,
 296     ) -> P<ast::Expr> {
 297         self.expr(span, ast::ExprKind::Struct(path, fields, None))
 298     }
 299     pub fn expr_struct_ident(
 300         &self,
 301         span: Span,
 302         id: Ident,
 303         fields: Vec<ast::Field>,
 304     ) -> P<ast::Expr> {
 305         self.expr_struct(span, self.path_ident(span, id), fields)
 306     }
 307
 308     pub fn expr_lit(&self, span: Span, lit_kind: ast::LitKind) -> P<ast::Expr> {
 309         let lit = ast::Lit::from_lit_kind(lit_kind, span);
 310         self.expr(span, ast::ExprKind::Lit(lit))
 311     }
 312     pub fn expr_usize(&self, span: Span, i: usize) -> P<ast::Expr> {
 313         self.expr_lit(
 314             span,
 315             ast::LitKind::Int(i as u128, ast::LitIntType::Unsigned(ast::UintTy::Usize)),
 316         )
 317     }
 318     pub fn expr_u32(&self, sp: Span, u: u32) -> P<ast::Expr> {
 319         self.expr_lit(sp, ast::LitKind::Int(u as u128, ast::LitIntType::Unsigned(ast::UintTy::U32)))
 320     }
 321     pub fn expr_bool(&self, sp: Span, value: bool) -> P<ast::Expr> {
 322         self.expr_lit(sp, ast::LitKind::Bool(value))
 323     }
 324
 325     pub fn expr_vec(&self, sp: Span, exprs: Vec<P<ast::Expr>>) -> P<ast::Expr> {
 326         self.expr(sp, ast::ExprKind::Array(exprs))
 327     }
 328     pub fn expr_vec_slice(&self, sp: Span, exprs: Vec<P<ast::Expr>>) -> P<ast::Expr> {
 329         self.expr_addr_of(sp, self.expr_vec(sp, exprs))
 330     }
 331     pub fn expr_str(&self, sp: Span, s: Symbol) -> P<ast::Expr> {
 332         self.expr_lit(sp, ast::LitKind::Str(s, ast::StrStyle::Cooked))
 333     }
 334
 335     pub fn expr_cast(&self, sp: Span, expr: P<ast::Expr>, ty: P<ast::Ty>) -> P<ast::Expr> {
 336         self.expr(sp, ast::ExprKind::Cast(expr, ty))
 337     }
 338
 339     pub fn expr_some(&self, sp: Span, expr: P<ast::Expr>) -> P<ast::Expr> {
 340         let some = self.std_path(&[sym::option, sym::Option, sym::Some]);
 341         self.expr_call_global(sp, some, vec![expr])
 342     }
 343
 344     pub fn expr_tuple(&self, sp: Span, exprs: Vec<P<ast::Expr>>) -> P<ast::Expr> {
 345         self.expr(sp, ast::ExprKind::Tup(exprs))
 346     }
 347
 348     pub fn expr_fail(&self, span: Span, msg: Symbol) -> P<ast::Expr> {
 349         self.expr_call_global(
 350             span,
 351             [sym::std, sym::rt, sym::begin_panic].iter().map(|s| Ident::new(*s, span)).collect(),
 352             vec![self.expr_str(span, msg)],
 353         )
 354     }
 355
 356     pub fn expr_unreachable(&self, span: Span) -> P<ast::Expr> {
 357         self.expr_fail(span, Symbol::intern("internal error: entered unreachable code"))
 358     }
 359
 360     pub fn expr_ok(&self, sp: Span, expr: P<ast::Expr>) -> P<ast::Expr> {
 361         let ok = self.std_path(&[sym::result, sym::Result, sym::Ok]);
 362         self.expr_call_global(sp, ok, vec![expr])
 363     }
 364
 365     pub fn expr_try(&self, sp: Span, head: P<ast::Expr>) -> P<ast::Expr> {
 366         let ok = self.std_path(&[sym::result, sym::Result, sym::Ok]);
 367         let ok_path = self.path_global(sp, ok);
 368         let err = self.std_path(&[sym::result, sym::Result, sym::Err]);
 369         let err_path = self.path_global(sp, err);
 370
 371         let binding_variable = self.ident_of("__try_var", sp);
 372         let binding_pat = self.pat_ident(sp, binding_variable);
 373         let binding_expr = self.expr_ident(sp, binding_variable);
 374
 375         // `Ok(__try_var)` pattern
 376         let ok_pat = self.pat_tuple_struct(sp, ok_path, vec![binding_pat.clone()]);
 377
 378         // `Err(__try_var)` (pattern and expression respectively)
 379         let err_pat = self.pat_tuple_struct(sp, err_path.clone(), vec![binding_pat]);
 380         let err_inner_expr =
 381             self.expr_call(sp, self.expr_path(err_path), vec![binding_expr.clone()]);
 382         // `return Err(__try_var)`
 383         let err_expr = self.expr(sp, ast::ExprKind::Ret(Some(err_inner_expr)));
 384
 385         // `Ok(__try_var) => __try_var`
 386         let ok_arm = self.arm(sp, ok_pat, binding_expr);
 387         // `Err(__try_var) => return Err(__try_var)`
 388         let err_arm = self.arm(sp, err_pat, err_expr);
 389
 390         // `match head { Ok() => ..., Err() => ... }`
 391         self.expr_match(sp, head, vec![ok_arm, err_arm])
 392     }
 393
 394     pub fn pat(&self, span: Span, kind: PatKind) -> P<ast::Pat> {
 395         P(ast::Pat { id: ast::DUMMY_NODE_ID, kind, span })
 396     }
 397     pub fn pat_wild(&self, span: Span) -> P<ast::Pat> {
 398         self.pat(span, PatKind::Wild)
 399     }
 400     pub fn pat_lit(&self, span: Span, expr: P<ast::Expr>) -> P<ast::Pat> {
 401         self.pat(span, PatKind::Lit(expr))
 402     }
 403     pub fn pat_ident(&self, span: Span, ident: Ident) -> P<ast::Pat> {
 404         let binding_mode = ast::BindingMode::ByValue(ast::Mutability::Not);
 405         self.pat_ident_binding_mode(span, ident, binding_mode)
 406     }
 407
 408     pub fn pat_ident_binding_mode(
 409         &self,
 410         span: Span,
 411         ident: Ident,
 412         bm: ast::BindingMode,
 413     ) -> P<ast::Pat> {
 414         let pat = PatKind::Ident(bm, ident.with_span_pos(span), None);
 415         self.pat(span, pat)
 416     }
 417     pub fn pat_path(&self, span: Span, path: ast::Path) -> P<ast::Pat> {
 418         self.pat(span, PatKind::Path(None, path))
 419     }
 420     pub fn pat_tuple_struct(
 421         &self,
 422         span: Span,
 423         path: ast::Path,
 424         subpats: Vec<P<ast::Pat>>,
 425     ) -> P<ast::Pat> {
 426         self.pat(span, PatKind::TupleStruct(path, subpats))
 427     }
 428     pub fn pat_struct(
 429         &self,
 430         span: Span,
 431         path: ast::Path,
 432         field_pats: Vec<ast::FieldPat>,
 433     ) -> P<ast::Pat> {
 434         self.pat(span, PatKind::Struct(path, field_pats, false))
 435     }
 436     pub fn pat_tuple(&self, span: Span, pats: Vec<P<ast::Pat>>) -> P<ast::Pat> {
 437         self.pat(span, PatKind::Tuple(pats))
 438     }
 439
 440     pub fn pat_some(&self, span: Span, pat: P<ast::Pat>) -> P<ast::Pat> {
 441         let some = self.std_path(&[sym::option, sym::Option, sym::Some]);
 442         let path = self.path_global(span, some);
 443         self.pat_tuple_struct(span, path, vec![pat])
 444     }
 445
 446     pub fn pat_none(&self, span: Span) -> P<ast::Pat> {
 447         let some = self.std_path(&[sym::option, sym::Option, sym::None]);
 448         let path = self.path_global(span, some);
 449         self.pat_path(span, path)
 450     }
 451
 452     pub fn pat_ok(&self, span: Span, pat: P<ast::Pat>) -> P<ast::Pat> {
 453         let some = self.std_path(&[sym::result, sym::Result, sym::Ok]);
 454         let path = self.path_global(span, some);
 455         self.pat_tuple_struct(span, path, vec![pat])
 456     }
 457
 458     pub fn pat_err(&self, span: Span, pat: P<ast::Pat>) -> P<ast::Pat> {
 459         let some = self.std_path(&[sym::result, sym::Result, sym::Err]);
 460         let path = self.path_global(span, some);
 461         self.pat_tuple_struct(span, path, vec![pat])
 462     }
 463
 464     pub fn arm(&self, span: Span, pat: P<ast::Pat>, expr: P<ast::Expr>) -> ast::Arm {
 465         ast::Arm {
 466             attrs: vec![],
 467             pat,
 468             guard: None,
 469             body: expr,
 470             span,
 471             id: ast::DUMMY_NODE_ID,
 472             is_placeholder: false,
 473         }
 474     }
 475
 476     pub fn arm_unreachable(&self, span: Span) -> ast::Arm {
 477         self.arm(span, self.pat_wild(span), self.expr_unreachable(span))
 478     }
 479
 480     pub fn expr_match(&self, span: Span, arg: P<ast::Expr>, arms: Vec<ast::Arm>) -> P<Expr> {
 481         self.expr(span, ast::ExprKind::Match(arg, arms))
 482     }
 483
 484     pub fn expr_if(
 485         &self,
 486         span: Span,
 487         cond: P<ast::Expr>,
 488         then: P<ast::Expr>,
 489         els: Option<P<ast::Expr>>,
 490     ) -> P<ast::Expr> {
 491         let els = els.map(|x| self.expr_block(self.block_expr(x)));
 492         self.expr(span, ast::ExprKind::If(cond, self.block_expr(then), els))
 493     }
 494
 495     pub fn lambda_fn_decl(
 496         &self,
 497         span: Span,
 498         fn_decl: P<ast::FnDecl>,
 499         body: P<ast::Expr>,
 500         fn_decl_span: Span,
 501     ) -> P<ast::Expr> {
 502         self.expr(
 503             span,
 504             ast::ExprKind::Closure(
 505                 ast::CaptureBy::Ref,
 506                 ast::Async::No,
 507                 ast::Movability::Movable,
 508                 fn_decl,
 509                 body,
 510                 fn_decl_span,
 511             ),
 512         )
 513     }
 514
 515     pub fn lambda(&self, span: Span, ids: Vec<Ident>, body: P<ast::Expr>) -> P<ast::Expr> {
 516         let fn_decl = self.fn_decl(
 517             ids.iter().map(|id| self.param(span, *id, self.ty(span, ast::TyKind::Infer))).collect(),
 518             ast::FnRetTy::Default(span),
 519         );
 520
 521         // FIXME -- We are using `span` as the span of the `|...|`
 522         // part of the lambda, but it probably (maybe?) corresponds to
 523         // the entire lambda body. Probably we should extend the API
 524         // here, but that's not entirely clear.
 525         self.expr(
 526             span,
 527             ast::ExprKind::Closure(
 528                 ast::CaptureBy::Ref,
 529                 ast::Async::No,
 530                 ast::Movability::Movable,
 531                 fn_decl,
 532                 body,
 533                 span,
 534             ),
 535         )
 536     }
 537
 538     pub fn lambda0(&self, span: Span, body: P<ast::Expr>) -> P<ast::Expr> {
 539         self.lambda(span, Vec::new(), body)
 540     }
 541
 542     pub fn lambda1(&self, span: Span, body: P<ast::Expr>, ident: Ident) -> P<ast::Expr> {
 543         self.lambda(span, vec![ident], body)
 544     }
 545
 546     pub fn lambda_stmts_1(&self, span: Span, stmts: Vec<ast::Stmt>, ident: Ident) -> P<ast::Expr> {
 547         self.lambda1(span, self.expr_block(self.block(span, stmts)), ident)
 548     }
 549
 550     pub fn param(&self, span: Span, ident: Ident, ty: P<ast::Ty>) -> ast::Param {
 551         let arg_pat = self.pat_ident(span, ident);
 552         ast::Param {
 553             attrs: AttrVec::default(),
 554             id: ast::DUMMY_NODE_ID,
 555             pat: arg_pat,
 556             span,
 557             ty,
 558             is_placeholder: false,
 559         }
 560     }
 561
 562     // FIXME: unused `self`
 563     pub fn fn_decl(&self, inputs: Vec<ast::Param>, output: ast::FnRetTy) -> P<ast::FnDecl> {
 564         P(ast::FnDecl { inputs, output })
 565     }
 566
 567     pub fn item(
 568         &self,
 569         span: Span,
 570         name: Ident,
 571         attrs: Vec<ast::Attribute>,
 572         kind: ast::ItemKind,
 573     ) -> P<ast::Item> {
 574         // FIXME: Would be nice if our generated code didn't violate
 575         // Rust coding conventions
 576         P(ast::Item {
 577             ident: name,
 578             attrs,
 579             id: ast::DUMMY_NODE_ID,
 580             kind,
 581             vis: respan(span.shrink_to_lo(), ast::VisibilityKind::Inherited),
 582             span,
 583             tokens: None,
 584         })
 585     }
 586
 587     pub fn variant(&self, span: Span, ident: Ident, tys: Vec<P<ast::Ty>>) -> ast::Variant {
 588         let vis_span = span.shrink_to_lo();
 589         let fields: Vec<_> = tys
 590             .into_iter()
 591             .map(|ty| ast::StructField {
 592                 span: ty.span,
 593                 ty,
 594                 ident: None,
 595                 vis: respan(vis_span, ast::VisibilityKind::Inherited),
 596                 attrs: Vec::new(),
 597                 id: ast::DUMMY_NODE_ID,
 598                 is_placeholder: false,
 599             })
 600             .collect();
 601
 602         let vdata = if fields.is_empty() {
 603             ast::VariantData::Unit(ast::DUMMY_NODE_ID)
 604         } else {
 605             ast::VariantData::Tuple(fields, ast::DUMMY_NODE_ID)
 606         };
 607
 608         ast::Variant {
 609             attrs: Vec::new(),
 610             data: vdata,
 611             disr_expr: None,
 612             id: ast::DUMMY_NODE_ID,
 613             ident,
 614             vis: respan(vis_span, ast::VisibilityKind::Inherited),
 615             span,
 616             is_placeholder: false,
 617         }
 618     }
 619
 620     pub fn item_static(
 621         &self,
 622         span: Span,
 623         name: Ident,
 624         ty: P<ast::Ty>,
 625         mutbl: ast::Mutability,
 626         expr: P<ast::Expr>,
 627     ) -> P<ast::Item> {
 628         self.item(span, name, Vec::new(), ast::ItemKind::Static(ty, mutbl, Some(expr)))
 629     }
 630
 631     pub fn item_const(
 632         &self,
 633         span: Span,
 634         name: Ident,
 635         ty: P<ast::Ty>,
 636         expr: P<ast::Expr>,
 637     ) -> P<ast::Item> {
 638         let def = ast::Defaultness::Final;
 639         self.item(span, name, Vec::new(), ast::ItemKind::Const(def, ty, Some(expr)))
 640     }
 641
 642     pub fn attribute(&self, mi: ast::MetaItem) -> ast::Attribute {
 643         attr::mk_attr_outer(mi)
 644     }
 645
 646     pub fn meta_word(&self, sp: Span, w: Symbol) -> ast::MetaItem {
 647         attr::mk_word_item(Ident::new(w, sp))
 648     }
 649 }