1 use crate::base::ExtCtxt;
3 use syntax::ast::{self, Ident, Expr, BlockCheckMode, UnOp, PatKind};
5 use syntax::source_map::{respan, Spanned};
7 use syntax::symbol::{kw, sym, Symbol};
10 use syntax_pos::{Pos, Span};
12 impl<'a> ExtCtxt<'a> {
13 pub fn path(&self, span: Span, strs: Vec<ast::Ident> ) -> ast::Path {
14 self.path_all(span, false, strs, vec![])
16 pub fn path_ident(&self, span: Span, id: ast::Ident) -> ast::Path {
17 self.path(span, vec![id])
19 pub fn path_global(&self, span: Span, strs: Vec<ast::Ident> ) -> ast::Path {
20 self.path_all(span, true, strs, vec![])
22 pub fn path_all(&self,
25 mut idents: Vec<ast::Ident> ,
26 args: Vec<ast::GenericArg>)
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);
32 segments.push(ast::PathSegment::path_root(span));
34 let last_ident = idents.pop().unwrap();
35 segments.extend(idents.into_iter().map(|ident| {
36 ast::PathSegment::from_ident(ident.with_span_pos(span))
38 let args = if !args.is_empty() {
39 ast::AngleBracketedArgs { args, constraints: Vec::new(), span }.into()
43 segments.push(ast::PathSegment {
44 ident: last_ident.with_span_pos(span),
45 id: ast::DUMMY_NODE_ID,
48 ast::Path { span, segments }
51 pub fn ty_mt(&self, ty: P<ast::Ty>, mutbl: ast::Mutability) -> ast::MutTy {
58 pub fn ty(&self, span: Span, kind: ast::TyKind) -> P<ast::Ty> {
60 id: ast::DUMMY_NODE_ID,
66 pub fn ty_path(&self, path: ast::Path) -> P<ast::Ty> {
67 self.ty(path.span, ast::TyKind::Path(None, path))
70 // Might need to take bounds as an argument in the future, if you ever want
71 // to generate a bounded existential trait type.
72 pub fn ty_ident(&self, span: Span, ident: ast::Ident)
74 self.ty_path(self.path_ident(span, ident))
77 pub fn anon_const(&self, span: Span, kind: ast::ExprKind) -> ast::AnonConst {
79 id: ast::DUMMY_NODE_ID,
81 id: ast::DUMMY_NODE_ID,
84 attrs: ThinVec::new(),
89 pub fn const_ident(&self, span: Span, ident: ast::Ident) -> ast::AnonConst {
90 self.anon_const(span, ast::ExprKind::Path(None, self.path_ident(span, ident)))
96 lifetime: Option<ast::Lifetime>,
97 mutbl: ast::Mutability)
100 ast::TyKind::Rptr(lifetime, self.ty_mt(ty, mutbl)))
106 mutbl: ast::Mutability)
109 ast::TyKind::Ptr(self.ty_mt(ty, mutbl)))
112 pub fn typaram(&self,
115 attrs: Vec<ast::Attribute>,
116 bounds: ast::GenericBounds,
117 default: Option<P<ast::Ty>>) -> ast::GenericParam {
119 ident: ident.with_span_pos(span),
120 id: ast::DUMMY_NODE_ID,
123 kind: ast::GenericParamKind::Type {
126 is_placeholder: false
130 pub fn trait_ref(&self, path: ast::Path) -> ast::TraitRef {
133 ref_id: ast::DUMMY_NODE_ID,
137 pub fn poly_trait_ref(&self, span: Span, path: ast::Path) -> ast::PolyTraitRef {
139 bound_generic_params: Vec::new(),
140 trait_ref: self.trait_ref(path),
145 pub fn trait_bound(&self, path: ast::Path) -> ast::GenericBound {
146 ast::GenericBound::Trait(self.poly_trait_ref(path.span, path),
147 ast::TraitBoundModifier::None)
150 pub fn lifetime(&self, span: Span, ident: ast::Ident) -> ast::Lifetime {
151 ast::Lifetime { id: ast::DUMMY_NODE_ID, ident: ident.with_span_pos(span) }
154 pub fn lifetime_def(&self,
157 attrs: Vec<ast::Attribute>,
158 bounds: ast::GenericBounds)
159 -> ast::GenericParam {
160 let lifetime = self.lifetime(span, ident);
162 ident: lifetime.ident,
166 kind: ast::GenericParamKind::Lifetime,
167 is_placeholder: false
171 pub fn stmt_expr(&self, expr: P<ast::Expr>) -> ast::Stmt {
173 id: ast::DUMMY_NODE_ID,
175 kind: ast::StmtKind::Expr(expr),
179 pub fn stmt_let(&self, sp: Span, mutbl: bool, ident: ast::Ident,
180 ex: P<ast::Expr>) -> ast::Stmt {
182 let binding_mode = ast::BindingMode::ByValue(ast::Mutability::Mutable);
183 self.pat_ident_binding_mode(sp, ident, binding_mode)
185 self.pat_ident(sp, ident)
187 let local = P(ast::Local {
191 id: ast::DUMMY_NODE_ID,
193 attrs: ThinVec::new(),
196 id: ast::DUMMY_NODE_ID,
197 kind: ast::StmtKind::Local(local),
202 // Generates `let _: Type;`, which is usually used for type assertions.
203 pub fn stmt_let_type_only(&self, span: Span, ty: P<ast::Ty>) -> ast::Stmt {
204 let local = P(ast::Local {
205 pat: self.pat_wild(span),
208 id: ast::DUMMY_NODE_ID,
210 attrs: ThinVec::new(),
213 id: ast::DUMMY_NODE_ID,
214 kind: ast::StmtKind::Local(local),
219 pub fn stmt_item(&self, sp: Span, item: P<ast::Item>) -> ast::Stmt {
221 id: ast::DUMMY_NODE_ID,
222 kind: ast::StmtKind::Item(item),
227 pub fn block_expr(&self, expr: P<ast::Expr>) -> P<ast::Block> {
228 self.block(expr.span, vec![ast::Stmt {
229 id: ast::DUMMY_NODE_ID,
231 kind: ast::StmtKind::Expr(expr),
234 pub fn block(&self, span: Span, stmts: Vec<ast::Stmt>) -> P<ast::Block> {
237 id: ast::DUMMY_NODE_ID,
238 rules: BlockCheckMode::Default,
243 pub fn expr(&self, span: Span, kind: ast::ExprKind) -> P<ast::Expr> {
245 id: ast::DUMMY_NODE_ID,
248 attrs: ThinVec::new(),
252 pub fn expr_path(&self, path: ast::Path) -> P<ast::Expr> {
253 self.expr(path.span, ast::ExprKind::Path(None, path))
256 pub fn expr_ident(&self, span: Span, id: ast::Ident) -> P<ast::Expr> {
257 self.expr_path(self.path_ident(span, id))
259 pub fn expr_self(&self, span: Span) -> P<ast::Expr> {
260 self.expr_ident(span, Ident::with_dummy_span(kw::SelfLower))
263 pub fn expr_binary(&self, sp: Span, op: ast::BinOpKind,
264 lhs: P<ast::Expr>, rhs: P<ast::Expr>) -> P<ast::Expr> {
265 self.expr(sp, ast::ExprKind::Binary(Spanned { node: op, span: sp }, lhs, rhs))
268 pub fn expr_deref(&self, sp: Span, e: P<ast::Expr>) -> P<ast::Expr> {
269 self.expr(sp, ast::ExprKind::Unary(UnOp::Deref, e))
272 pub fn expr_addr_of(&self, sp: Span, e: P<ast::Expr>) -> P<ast::Expr> {
273 self.expr(sp, ast::ExprKind::AddrOf(ast::Mutability::Immutable, e))
277 &self, span: Span, expr: P<ast::Expr>, args: Vec<P<ast::Expr>>,
279 self.expr(span, ast::ExprKind::Call(expr, args))
281 pub fn expr_call_ident(&self, span: Span, id: ast::Ident,
282 args: Vec<P<ast::Expr>>) -> P<ast::Expr> {
283 self.expr(span, ast::ExprKind::Call(self.expr_ident(span, id), args))
285 pub fn expr_call_global(&self, sp: Span, fn_path: Vec<ast::Ident> ,
286 args: Vec<P<ast::Expr>> ) -> P<ast::Expr> {
287 let pathexpr = self.expr_path(self.path_global(sp, fn_path));
288 self.expr_call(sp, pathexpr, args)
290 pub fn expr_method_call(&self, span: Span,
293 mut args: Vec<P<ast::Expr>> ) -> P<ast::Expr> {
294 args.insert(0, expr);
295 let segment = ast::PathSegment::from_ident(ident.with_span_pos(span));
296 self.expr(span, ast::ExprKind::MethodCall(segment, args))
298 pub fn expr_block(&self, b: P<ast::Block>) -> P<ast::Expr> {
299 self.expr(b.span, ast::ExprKind::Block(b, None))
301 pub fn field_imm(&self, span: Span, ident: Ident, e: P<ast::Expr>) -> ast::Field {
303 ident: ident.with_span_pos(span),
307 attrs: ThinVec::new(),
308 id: ast::DUMMY_NODE_ID,
309 is_placeholder: false,
313 &self, span: Span, path: ast::Path, fields: Vec<ast::Field>
315 self.expr(span, ast::ExprKind::Struct(path, fields, None))
317 pub fn expr_struct_ident(&self, span: Span,
318 id: ast::Ident, fields: Vec<ast::Field>) -> P<ast::Expr> {
319 self.expr_struct(span, self.path_ident(span, id), fields)
322 pub fn expr_lit(&self, span: Span, lit_kind: ast::LitKind) -> P<ast::Expr> {
323 let lit = ast::Lit::from_lit_kind(lit_kind, span);
324 self.expr(span, ast::ExprKind::Lit(lit))
326 pub fn expr_usize(&self, span: Span, i: usize) -> P<ast::Expr> {
327 self.expr_lit(span, ast::LitKind::Int(i as u128,
328 ast::LitIntType::Unsigned(ast::UintTy::Usize)))
330 pub fn expr_u32(&self, sp: Span, u: u32) -> P<ast::Expr> {
331 self.expr_lit(sp, ast::LitKind::Int(u as u128,
332 ast::LitIntType::Unsigned(ast::UintTy::U32)))
334 pub fn expr_bool(&self, sp: Span, value: bool) -> P<ast::Expr> {
335 self.expr_lit(sp, ast::LitKind::Bool(value))
338 pub fn expr_vec(&self, sp: Span, exprs: Vec<P<ast::Expr>>) -> P<ast::Expr> {
339 self.expr(sp, ast::ExprKind::Array(exprs))
341 pub fn expr_vec_slice(&self, sp: Span, exprs: Vec<P<ast::Expr>>) -> P<ast::Expr> {
342 self.expr_addr_of(sp, self.expr_vec(sp, exprs))
344 pub fn expr_str(&self, sp: Span, s: Symbol) -> P<ast::Expr> {
345 self.expr_lit(sp, ast::LitKind::Str(s, ast::StrStyle::Cooked))
348 pub fn expr_cast(&self, sp: Span, expr: P<ast::Expr>, ty: P<ast::Ty>) -> P<ast::Expr> {
349 self.expr(sp, ast::ExprKind::Cast(expr, ty))
352 pub fn expr_some(&self, sp: Span, expr: P<ast::Expr>) -> P<ast::Expr> {
353 let some = self.std_path(&[sym::option, sym::Option, sym::Some]);
354 self.expr_call_global(sp, some, vec![expr])
357 pub fn expr_tuple(&self, sp: Span, exprs: Vec<P<ast::Expr>>) -> P<ast::Expr> {
358 self.expr(sp, ast::ExprKind::Tup(exprs))
361 pub fn expr_fail(&self, span: Span, msg: Symbol) -> P<ast::Expr> {
362 let loc = self.source_map().lookup_char_pos(span.lo());
363 let expr_file = self.expr_str(span, Symbol::intern(&loc.file.name.to_string()));
364 let expr_line = self.expr_u32(span, loc.line as u32);
365 let expr_col = self.expr_u32(span, loc.col.to_usize() as u32 + 1);
366 let expr_loc_tuple = self.expr_tuple(span, vec![expr_file, expr_line, expr_col]);
367 let expr_loc_ptr = self.expr_addr_of(span, expr_loc_tuple);
368 self.expr_call_global(
370 [sym::std, sym::rt, sym::begin_panic].iter().map(|s| Ident::new(*s, span)).collect(),
372 self.expr_str(span, msg),
376 pub fn expr_unreachable(&self, span: Span) -> P<ast::Expr> {
377 self.expr_fail(span, Symbol::intern("internal error: entered unreachable code"))
380 pub fn expr_ok(&self, sp: Span, expr: P<ast::Expr>) -> P<ast::Expr> {
381 let ok = self.std_path(&[sym::result, sym::Result, sym::Ok]);
382 self.expr_call_global(sp, ok, vec![expr])
385 pub fn expr_try(&self, sp: Span, head: P<ast::Expr>) -> P<ast::Expr> {
386 let ok = self.std_path(&[sym::result, sym::Result, sym::Ok]);
387 let ok_path = self.path_global(sp, ok);
388 let err = self.std_path(&[sym::result, sym::Result, sym::Err]);
389 let err_path = self.path_global(sp, err);
391 let binding_variable = self.ident_of("__try_var", sp);
392 let binding_pat = self.pat_ident(sp, binding_variable);
393 let binding_expr = self.expr_ident(sp, binding_variable);
395 // `Ok(__try_var)` pattern
396 let ok_pat = self.pat_tuple_struct(sp, ok_path, vec![binding_pat.clone()]);
398 // `Err(__try_var)` (pattern and expression respectively)
399 let err_pat = self.pat_tuple_struct(sp, err_path.clone(), vec![binding_pat]);
400 let err_inner_expr = self.expr_call(sp, self.expr_path(err_path),
401 vec![binding_expr.clone()]);
402 // `return Err(__try_var)`
403 let err_expr = self.expr(sp, ast::ExprKind::Ret(Some(err_inner_expr)));
405 // `Ok(__try_var) => __try_var`
406 let ok_arm = self.arm(sp, ok_pat, binding_expr);
407 // `Err(__try_var) => return Err(__try_var)`
408 let err_arm = self.arm(sp, err_pat, err_expr);
410 // `match head { Ok() => ..., Err() => ... }`
411 self.expr_match(sp, head, vec![ok_arm, err_arm])
415 pub fn pat(&self, span: Span, kind: PatKind) -> P<ast::Pat> {
416 P(ast::Pat { id: ast::DUMMY_NODE_ID, kind, span })
418 pub fn pat_wild(&self, span: Span) -> P<ast::Pat> {
419 self.pat(span, PatKind::Wild)
421 pub fn pat_lit(&self, span: Span, expr: P<ast::Expr>) -> P<ast::Pat> {
422 self.pat(span, PatKind::Lit(expr))
424 pub fn pat_ident(&self, span: Span, ident: ast::Ident) -> P<ast::Pat> {
425 let binding_mode = ast::BindingMode::ByValue(ast::Mutability::Immutable);
426 self.pat_ident_binding_mode(span, ident, binding_mode)
429 pub fn pat_ident_binding_mode(&self,
432 bm: ast::BindingMode) -> P<ast::Pat> {
433 let pat = PatKind::Ident(bm, ident.with_span_pos(span), None);
436 pub fn pat_path(&self, span: Span, path: ast::Path) -> P<ast::Pat> {
437 self.pat(span, PatKind::Path(None, path))
439 pub fn pat_tuple_struct(&self, span: Span, path: ast::Path,
440 subpats: Vec<P<ast::Pat>>) -> P<ast::Pat> {
441 self.pat(span, PatKind::TupleStruct(path, subpats))
443 pub fn pat_struct(&self, span: Span, path: ast::Path,
444 field_pats: Vec<ast::FieldPat>) -> P<ast::Pat> {
445 self.pat(span, PatKind::Struct(path, field_pats, false))
447 pub fn pat_tuple(&self, span: Span, pats: Vec<P<ast::Pat>>) -> P<ast::Pat> {
448 self.pat(span, PatKind::Tuple(pats))
451 pub fn pat_some(&self, span: Span, pat: P<ast::Pat>) -> P<ast::Pat> {
452 let some = self.std_path(&[sym::option, sym::Option, sym::Some]);
453 let path = self.path_global(span, some);
454 self.pat_tuple_struct(span, path, vec![pat])
457 pub fn pat_none(&self, span: Span) -> P<ast::Pat> {
458 let some = self.std_path(&[sym::option, sym::Option, sym::None]);
459 let path = self.path_global(span, some);
460 self.pat_path(span, path)
463 pub fn pat_ok(&self, span: Span, pat: P<ast::Pat>) -> P<ast::Pat> {
464 let some = self.std_path(&[sym::result, sym::Result, sym::Ok]);
465 let path = self.path_global(span, some);
466 self.pat_tuple_struct(span, path, vec![pat])
469 pub fn pat_err(&self, span: Span, pat: P<ast::Pat>) -> P<ast::Pat> {
470 let some = self.std_path(&[sym::result, sym::Result, sym::Err]);
471 let path = self.path_global(span, some);
472 self.pat_tuple_struct(span, path, vec![pat])
475 pub fn arm(&self, span: Span, pat: P<ast::Pat>, expr: P<ast::Expr>) -> ast::Arm {
482 id: ast::DUMMY_NODE_ID,
483 is_placeholder: false,
487 pub fn arm_unreachable(&self, span: Span) -> ast::Arm {
488 self.arm(span, self.pat_wild(span), self.expr_unreachable(span))
491 pub fn expr_match(&self, span: Span, arg: P<ast::Expr>, arms: Vec<ast::Arm>) -> P<Expr> {
492 self.expr(span, ast::ExprKind::Match(arg, arms))
495 pub fn expr_if(&self, span: Span, cond: P<ast::Expr>,
496 then: P<ast::Expr>, els: Option<P<ast::Expr>>) -> P<ast::Expr> {
497 let els = els.map(|x| self.expr_block(self.block_expr(x)));
498 self.expr(span, ast::ExprKind::If(cond, self.block_expr(then), els))
501 pub fn lambda_fn_decl(&self,
503 fn_decl: P<ast::FnDecl>,
505 fn_decl_span: Span) // span of the `|...|` part
507 self.expr(span, ast::ExprKind::Closure(ast::CaptureBy::Ref,
508 ast::IsAsync::NotAsync,
509 ast::Movability::Movable,
517 ids: Vec<ast::Ident>,
520 let fn_decl = self.fn_decl(
521 ids.iter().map(|id| self.param(span, *id, self.ty(span, ast::TyKind::Infer))).collect(),
522 ast::FunctionRetTy::Default(span));
524 // FIXME -- We are using `span` as the span of the `|...|`
525 // part of the lambda, but it probably (maybe?) corresponds to
526 // the entire lambda body. Probably we should extend the API
527 // here, but that's not entirely clear.
528 self.expr(span, ast::ExprKind::Closure(ast::CaptureBy::Ref,
529 ast::IsAsync::NotAsync,
530 ast::Movability::Movable,
536 pub fn lambda0(&self, span: Span, body: P<ast::Expr>) -> P<ast::Expr> {
537 self.lambda(span, Vec::new(), body)
540 pub fn lambda1(&self, span: Span, body: P<ast::Expr>, ident: ast::Ident) -> P<ast::Expr> {
541 self.lambda(span, vec![ident], body)
544 pub fn lambda_stmts_1(&self, span: Span, stmts: Vec<ast::Stmt>,
545 ident: ast::Ident) -> P<ast::Expr> {
546 self.lambda1(span, self.expr_block(self.block(span, stmts)), ident)
549 pub fn param(&self, span: Span, ident: ast::Ident, ty: P<ast::Ty>) -> ast::Param {
550 let arg_pat = self.pat_ident(span, ident);
552 attrs: ThinVec::default(),
553 id: ast::DUMMY_NODE_ID,
557 is_placeholder: false,
561 // FIXME: unused `self`
562 pub fn fn_decl(&self, inputs: Vec<ast::Param>, output: ast::FunctionRetTy) -> P<ast::FnDecl> {
569 pub fn item(&self, span: Span, name: Ident,
570 attrs: Vec<ast::Attribute>, kind: ast::ItemKind) -> P<ast::Item> {
571 // FIXME: Would be nice if our generated code didn't violate
572 // Rust coding conventions
576 id: ast::DUMMY_NODE_ID,
578 vis: respan(span.shrink_to_lo(), ast::VisibilityKind::Inherited),
584 pub fn variant(&self, span: Span, ident: Ident, tys: Vec<P<ast::Ty>> ) -> ast::Variant {
585 let fields: Vec<_> = tys.into_iter().map(|ty| {
590 vis: respan(span.shrink_to_lo(), ast::VisibilityKind::Inherited),
592 id: ast::DUMMY_NODE_ID,
593 is_placeholder: false,
597 let vdata = if fields.is_empty() {
598 ast::VariantData::Unit(ast::DUMMY_NODE_ID)
600 ast::VariantData::Tuple(fields, ast::DUMMY_NODE_ID)
607 id: ast::DUMMY_NODE_ID,
610 is_placeholder: false,
614 pub fn item_static(&self,
618 mutbl: ast::Mutability,
621 self.item(span, name, Vec::new(), ast::ItemKind::Static(ty, mutbl, expr))
624 pub fn item_const(&self,
630 self.item(span, name, Vec::new(), ast::ItemKind::Const(ty, expr))
633 pub fn attribute(&self, mi: ast::MetaItem) -> ast::Attribute {
634 attr::mk_attr_outer(mi)
637 pub fn meta_word(&self, sp: Span, w: ast::Name) -> ast::MetaItem {
638 attr::mk_word_item(Ident::new(w, sp))