rust/compiler/rustc_expand/src/build.rs
Maybe Waffle 40ae7b5b8e Parse closure binders
This is first step in implementing RFC 3216.
- Parse `for<'a>` before closures in ast
  - Error in lowering
- Add `closure_lifetime_binder` feature
2022-07-12 16:25:16 +04:00

617 lines
20 KiB
Rust

use crate::base::ExtCtxt;
use rustc_ast::attr;
use rustc_ast::ptr::P;
use rustc_ast::{self as ast, AttrVec, BlockCheckMode, Expr, LocalKind, PatKind, UnOp};
use rustc_span::source_map::Spanned;
use rustc_span::symbol::{kw, sym, Ident, Symbol};
use rustc_span::Span;
impl<'a> ExtCtxt<'a> {
pub fn path(&self, span: Span, strs: Vec<Ident>) -> ast::Path {
self.path_all(span, false, strs, vec![])
}
pub fn path_ident(&self, span: Span, id: Ident) -> ast::Path {
self.path(span, vec![id])
}
pub fn path_global(&self, span: Span, strs: Vec<Ident>) -> ast::Path {
self.path_all(span, true, strs, vec![])
}
pub fn path_all(
&self,
span: Span,
global: bool,
mut idents: Vec<Ident>,
args: Vec<ast::GenericArg>,
) -> ast::Path {
assert!(!idents.is_empty());
let add_root = global && !idents[0].is_path_segment_keyword();
let mut segments = Vec::with_capacity(idents.len() + add_root as usize);
if add_root {
segments.push(ast::PathSegment::path_root(span));
}
let last_ident = idents.pop().unwrap();
segments.extend(
idents.into_iter().map(|ident| ast::PathSegment::from_ident(ident.with_span_pos(span))),
);
let args = if !args.is_empty() {
let args = args.into_iter().map(ast::AngleBracketedArg::Arg).collect();
ast::AngleBracketedArgs { args, span }.into()
} else {
None
};
segments.push(ast::PathSegment {
ident: last_ident.with_span_pos(span),
id: ast::DUMMY_NODE_ID,
args,
});
ast::Path { span, segments, tokens: None }
}
pub fn ty_mt(&self, ty: P<ast::Ty>, mutbl: ast::Mutability) -> ast::MutTy {
ast::MutTy { ty, mutbl }
}
pub fn ty(&self, span: Span, kind: ast::TyKind) -> P<ast::Ty> {
P(ast::Ty { id: ast::DUMMY_NODE_ID, span, kind, tokens: None })
}
pub fn ty_infer(&self, span: Span) -> P<ast::Ty> {
self.ty(span, ast::TyKind::Infer)
}
pub fn ty_path(&self, path: ast::Path) -> P<ast::Ty> {
self.ty(path.span, ast::TyKind::Path(None, path))
}
// Might need to take bounds as an argument in the future, if you ever want
// to generate a bounded existential trait type.
pub fn ty_ident(&self, span: Span, ident: Ident) -> P<ast::Ty> {
self.ty_path(self.path_ident(span, ident))
}
pub fn anon_const(&self, span: Span, kind: ast::ExprKind) -> ast::AnonConst {
ast::AnonConst {
id: ast::DUMMY_NODE_ID,
value: P(ast::Expr {
id: ast::DUMMY_NODE_ID,
kind,
span,
attrs: AttrVec::new(),
tokens: None,
}),
}
}
pub fn const_ident(&self, span: Span, ident: Ident) -> ast::AnonConst {
self.anon_const(span, ast::ExprKind::Path(None, self.path_ident(span, ident)))
}
pub fn ty_rptr(
&self,
span: Span,
ty: P<ast::Ty>,
lifetime: Option<ast::Lifetime>,
mutbl: ast::Mutability,
) -> P<ast::Ty> {
self.ty(span, ast::TyKind::Rptr(lifetime, self.ty_mt(ty, mutbl)))
}
pub fn ty_ptr(&self, span: Span, ty: P<ast::Ty>, mutbl: ast::Mutability) -> P<ast::Ty> {
self.ty(span, ast::TyKind::Ptr(self.ty_mt(ty, mutbl)))
}
pub fn typaram(
&self,
span: Span,
ident: Ident,
attrs: Vec<ast::Attribute>,
bounds: ast::GenericBounds,
default: Option<P<ast::Ty>>,
) -> ast::GenericParam {
ast::GenericParam {
ident: ident.with_span_pos(span),
id: ast::DUMMY_NODE_ID,
attrs: attrs.into(),
bounds,
kind: ast::GenericParamKind::Type { default },
is_placeholder: false,
colon_span: None,
}
}
pub fn trait_ref(&self, path: ast::Path) -> ast::TraitRef {
ast::TraitRef { path, ref_id: ast::DUMMY_NODE_ID }
}
pub fn poly_trait_ref(&self, span: Span, path: ast::Path) -> ast::PolyTraitRef {
ast::PolyTraitRef {
bound_generic_params: Vec::new(),
trait_ref: self.trait_ref(path),
span,
}
}
pub fn trait_bound(&self, path: ast::Path) -> ast::GenericBound {
ast::GenericBound::Trait(
self.poly_trait_ref(path.span, path),
ast::TraitBoundModifier::None,
)
}
pub fn lifetime(&self, span: Span, ident: Ident) -> ast::Lifetime {
ast::Lifetime { id: ast::DUMMY_NODE_ID, ident: ident.with_span_pos(span) }
}
pub fn lifetime_static(&self, span: Span) -> ast::Lifetime {
self.lifetime(span, Ident::new(kw::StaticLifetime, span))
}
pub fn stmt_expr(&self, expr: P<ast::Expr>) -> ast::Stmt {
ast::Stmt { id: ast::DUMMY_NODE_ID, span: expr.span, kind: ast::StmtKind::Expr(expr) }
}
pub fn stmt_let_pat(&self, sp: Span, pat: P<ast::Pat>, ex: P<ast::Expr>) -> ast::Stmt {
let local = P(ast::Local {
pat,
ty: None,
id: ast::DUMMY_NODE_ID,
kind: LocalKind::Init(ex),
span: sp,
attrs: AttrVec::new(),
tokens: None,
});
self.stmt_local(local, sp)
}
pub fn stmt_let(&self, sp: Span, mutbl: bool, ident: Ident, ex: P<ast::Expr>) -> ast::Stmt {
self.stmt_let_ty(sp, mutbl, ident, None, ex)
}
pub fn stmt_let_ty(
&self,
sp: Span,
mutbl: bool,
ident: Ident,
ty: Option<P<ast::Ty>>,
ex: P<ast::Expr>,
) -> ast::Stmt {
let pat = if mutbl {
let binding_mode = ast::BindingMode::ByValue(ast::Mutability::Mut);
self.pat_ident_binding_mode(sp, ident, binding_mode)
} else {
self.pat_ident(sp, ident)
};
let local = P(ast::Local {
pat,
ty,
id: ast::DUMMY_NODE_ID,
kind: LocalKind::Init(ex),
span: sp,
attrs: AttrVec::new(),
tokens: None,
});
self.stmt_local(local, sp)
}
// Generates `let _: Type;`, which is usually used for type assertions.
pub fn stmt_let_type_only(&self, span: Span, ty: P<ast::Ty>) -> ast::Stmt {
let local = P(ast::Local {
pat: self.pat_wild(span),
ty: Some(ty),
id: ast::DUMMY_NODE_ID,
kind: LocalKind::Decl,
span,
attrs: AttrVec::new(),
tokens: None,
});
self.stmt_local(local, span)
}
pub fn stmt_local(&self, local: P<ast::Local>, span: Span) -> ast::Stmt {
ast::Stmt { id: ast::DUMMY_NODE_ID, kind: ast::StmtKind::Local(local), span }
}
pub fn stmt_item(&self, sp: Span, item: P<ast::Item>) -> ast::Stmt {
ast::Stmt { id: ast::DUMMY_NODE_ID, kind: ast::StmtKind::Item(item), span: sp }
}
pub fn block_expr(&self, expr: P<ast::Expr>) -> P<ast::Block> {
self.block(
expr.span,
vec![ast::Stmt {
id: ast::DUMMY_NODE_ID,
span: expr.span,
kind: ast::StmtKind::Expr(expr),
}],
)
}
pub fn block(&self, span: Span, stmts: Vec<ast::Stmt>) -> P<ast::Block> {
P(ast::Block {
stmts,
id: ast::DUMMY_NODE_ID,
rules: BlockCheckMode::Default,
span,
tokens: None,
could_be_bare_literal: false,
})
}
pub fn expr(&self, span: Span, kind: ast::ExprKind) -> P<ast::Expr> {
P(ast::Expr { id: ast::DUMMY_NODE_ID, kind, span, attrs: AttrVec::new(), tokens: None })
}
pub fn expr_path(&self, path: ast::Path) -> P<ast::Expr> {
self.expr(path.span, ast::ExprKind::Path(None, path))
}
pub fn expr_ident(&self, span: Span, id: Ident) -> P<ast::Expr> {
self.expr_path(self.path_ident(span, id))
}
pub fn expr_self(&self, span: Span) -> P<ast::Expr> {
self.expr_ident(span, Ident::with_dummy_span(kw::SelfLower))
}
pub fn expr_binary(
&self,
sp: Span,
op: ast::BinOpKind,
lhs: P<ast::Expr>,
rhs: P<ast::Expr>,
) -> P<ast::Expr> {
self.expr(sp, ast::ExprKind::Binary(Spanned { node: op, span: sp }, lhs, rhs))
}
pub fn expr_deref(&self, sp: Span, e: P<ast::Expr>) -> P<ast::Expr> {
self.expr(sp, ast::ExprKind::Unary(UnOp::Deref, e))
}
pub fn expr_addr_of(&self, sp: Span, e: P<ast::Expr>) -> P<ast::Expr> {
self.expr(sp, ast::ExprKind::AddrOf(ast::BorrowKind::Ref, ast::Mutability::Not, e))
}
pub fn expr_call(
&self,
span: Span,
expr: P<ast::Expr>,
args: Vec<P<ast::Expr>>,
) -> P<ast::Expr> {
self.expr(span, ast::ExprKind::Call(expr, args))
}
pub fn expr_call_ident(&self, span: Span, id: Ident, args: Vec<P<ast::Expr>>) -> P<ast::Expr> {
self.expr(span, ast::ExprKind::Call(self.expr_ident(span, id), args))
}
pub fn expr_call_global(
&self,
sp: Span,
fn_path: Vec<Ident>,
args: Vec<P<ast::Expr>>,
) -> P<ast::Expr> {
let pathexpr = self.expr_path(self.path_global(sp, fn_path));
self.expr_call(sp, pathexpr, args)
}
pub fn expr_block(&self, b: P<ast::Block>) -> P<ast::Expr> {
self.expr(b.span, ast::ExprKind::Block(b, None))
}
pub fn field_imm(&self, span: Span, ident: Ident, e: P<ast::Expr>) -> ast::ExprField {
ast::ExprField {
ident: ident.with_span_pos(span),
expr: e,
span,
is_shorthand: false,
attrs: AttrVec::new(),
id: ast::DUMMY_NODE_ID,
is_placeholder: false,
}
}
pub fn expr_struct(
&self,
span: Span,
path: ast::Path,
fields: Vec<ast::ExprField>,
) -> P<ast::Expr> {
self.expr(
span,
ast::ExprKind::Struct(P(ast::StructExpr {
qself: None,
path,
fields,
rest: ast::StructRest::None,
})),
)
}
pub fn expr_struct_ident(
&self,
span: Span,
id: Ident,
fields: Vec<ast::ExprField>,
) -> P<ast::Expr> {
self.expr_struct(span, self.path_ident(span, id), fields)
}
pub fn expr_lit(&self, span: Span, lit_kind: ast::LitKind) -> P<ast::Expr> {
let lit = ast::Lit::from_lit_kind(lit_kind, span);
self.expr(span, ast::ExprKind::Lit(lit))
}
pub fn expr_usize(&self, span: Span, i: usize) -> P<ast::Expr> {
self.expr_lit(
span,
ast::LitKind::Int(i as u128, ast::LitIntType::Unsigned(ast::UintTy::Usize)),
)
}
pub fn expr_u32(&self, sp: Span, u: u32) -> P<ast::Expr> {
self.expr_lit(sp, ast::LitKind::Int(u as u128, ast::LitIntType::Unsigned(ast::UintTy::U32)))
}
pub fn expr_bool(&self, sp: Span, value: bool) -> P<ast::Expr> {
self.expr_lit(sp, ast::LitKind::Bool(value))
}
/// `[expr1, expr2, ...]`
pub fn expr_array(&self, sp: Span, exprs: Vec<P<ast::Expr>>) -> P<ast::Expr> {
self.expr(sp, ast::ExprKind::Array(exprs))
}
/// `&[expr1, expr2, ...]`
pub fn expr_array_ref(&self, sp: Span, exprs: Vec<P<ast::Expr>>) -> P<ast::Expr> {
self.expr_addr_of(sp, self.expr_array(sp, exprs))
}
pub fn expr_str(&self, sp: Span, s: Symbol) -> P<ast::Expr> {
self.expr_lit(sp, ast::LitKind::Str(s, ast::StrStyle::Cooked))
}
pub fn expr_cast(&self, sp: Span, expr: P<ast::Expr>, ty: P<ast::Ty>) -> P<ast::Expr> {
self.expr(sp, ast::ExprKind::Cast(expr, ty))
}
pub fn expr_some(&self, sp: Span, expr: P<ast::Expr>) -> P<ast::Expr> {
let some = self.std_path(&[sym::option, sym::Option, sym::Some]);
self.expr_call_global(sp, some, vec![expr])
}
pub fn expr_none(&self, sp: Span) -> P<ast::Expr> {
let none = self.std_path(&[sym::option, sym::Option, sym::None]);
self.expr_path(self.path_global(sp, none))
}
pub fn expr_tuple(&self, sp: Span, exprs: Vec<P<ast::Expr>>) -> P<ast::Expr> {
self.expr(sp, ast::ExprKind::Tup(exprs))
}
pub fn expr_fail(&self, span: Span, msg: Symbol) -> P<ast::Expr> {
self.expr_call_global(
span,
[sym::std, sym::rt, sym::begin_panic].iter().map(|s| Ident::new(*s, span)).collect(),
vec![self.expr_str(span, msg)],
)
}
pub fn expr_unreachable(&self, span: Span) -> P<ast::Expr> {
self.expr_fail(span, Symbol::intern("internal error: entered unreachable code"))
}
pub fn expr_ok(&self, sp: Span, expr: P<ast::Expr>) -> P<ast::Expr> {
let ok = self.std_path(&[sym::result, sym::Result, sym::Ok]);
self.expr_call_global(sp, ok, vec![expr])
}
pub fn expr_try(&self, sp: Span, head: P<ast::Expr>) -> P<ast::Expr> {
let ok = self.std_path(&[sym::result, sym::Result, sym::Ok]);
let ok_path = self.path_global(sp, ok);
let err = self.std_path(&[sym::result, sym::Result, sym::Err]);
let err_path = self.path_global(sp, err);
let binding_variable = Ident::new(sym::__try_var, sp);
let binding_pat = self.pat_ident(sp, binding_variable);
let binding_expr = self.expr_ident(sp, binding_variable);
// `Ok(__try_var)` pattern
let ok_pat = self.pat_tuple_struct(sp, ok_path, vec![binding_pat.clone()]);
// `Err(__try_var)` (pattern and expression respectively)
let err_pat = self.pat_tuple_struct(sp, err_path.clone(), vec![binding_pat]);
let err_inner_expr =
self.expr_call(sp, self.expr_path(err_path), vec![binding_expr.clone()]);
// `return Err(__try_var)`
let err_expr = self.expr(sp, ast::ExprKind::Ret(Some(err_inner_expr)));
// `Ok(__try_var) => __try_var`
let ok_arm = self.arm(sp, ok_pat, binding_expr);
// `Err(__try_var) => return Err(__try_var)`
let err_arm = self.arm(sp, err_pat, err_expr);
// `match head { Ok() => ..., Err() => ... }`
self.expr_match(sp, head, vec![ok_arm, err_arm])
}
pub fn pat(&self, span: Span, kind: PatKind) -> P<ast::Pat> {
P(ast::Pat { id: ast::DUMMY_NODE_ID, kind, span, tokens: None })
}
pub fn pat_wild(&self, span: Span) -> P<ast::Pat> {
self.pat(span, PatKind::Wild)
}
pub fn pat_lit(&self, span: Span, expr: P<ast::Expr>) -> P<ast::Pat> {
self.pat(span, PatKind::Lit(expr))
}
pub fn pat_ident(&self, span: Span, ident: Ident) -> P<ast::Pat> {
let binding_mode = ast::BindingMode::ByValue(ast::Mutability::Not);
self.pat_ident_binding_mode(span, ident, binding_mode)
}
pub fn pat_ident_binding_mode(
&self,
span: Span,
ident: Ident,
bm: ast::BindingMode,
) -> P<ast::Pat> {
let pat = PatKind::Ident(bm, ident.with_span_pos(span), None);
self.pat(span, pat)
}
pub fn pat_path(&self, span: Span, path: ast::Path) -> P<ast::Pat> {
self.pat(span, PatKind::Path(None, path))
}
pub fn pat_tuple_struct(
&self,
span: Span,
path: ast::Path,
subpats: Vec<P<ast::Pat>>,
) -> P<ast::Pat> {
self.pat(span, PatKind::TupleStruct(None, path, subpats))
}
pub fn pat_struct(
&self,
span: Span,
path: ast::Path,
field_pats: Vec<ast::PatField>,
) -> P<ast::Pat> {
self.pat(span, PatKind::Struct(None, path, field_pats, false))
}
pub fn pat_tuple(&self, span: Span, pats: Vec<P<ast::Pat>>) -> P<ast::Pat> {
self.pat(span, PatKind::Tuple(pats))
}
pub fn pat_some(&self, span: Span, pat: P<ast::Pat>) -> P<ast::Pat> {
let some = self.std_path(&[sym::option, sym::Option, sym::Some]);
let path = self.path_global(span, some);
self.pat_tuple_struct(span, path, vec![pat])
}
pub fn arm(&self, span: Span, pat: P<ast::Pat>, expr: P<ast::Expr>) -> ast::Arm {
ast::Arm {
attrs: AttrVec::new(),
pat,
guard: None,
body: expr,
span,
id: ast::DUMMY_NODE_ID,
is_placeholder: false,
}
}
pub fn arm_unreachable(&self, span: Span) -> ast::Arm {
self.arm(span, self.pat_wild(span), self.expr_unreachable(span))
}
pub fn expr_match(&self, span: Span, arg: P<ast::Expr>, arms: Vec<ast::Arm>) -> P<Expr> {
self.expr(span, ast::ExprKind::Match(arg, arms))
}
pub fn expr_if(
&self,
span: Span,
cond: P<ast::Expr>,
then: P<ast::Expr>,
els: Option<P<ast::Expr>>,
) -> P<ast::Expr> {
let els = els.map(|x| self.expr_block(self.block_expr(x)));
self.expr(span, ast::ExprKind::If(cond, self.block_expr(then), els))
}
pub fn lambda(&self, span: Span, ids: Vec<Ident>, body: P<ast::Expr>) -> P<ast::Expr> {
let fn_decl = self.fn_decl(
ids.iter().map(|id| self.param(span, *id, self.ty(span, ast::TyKind::Infer))).collect(),
ast::FnRetTy::Default(span),
);
// FIXME -- We are using `span` as the span of the `|...|`
// part of the lambda, but it probably (maybe?) corresponds to
// the entire lambda body. Probably we should extend the API
// here, but that's not entirely clear.
self.expr(
span,
ast::ExprKind::Closure(
ast::ClosureBinder::NotPresent,
ast::CaptureBy::Ref,
ast::Async::No,
ast::Movability::Movable,
fn_decl,
body,
span,
),
)
}
pub fn lambda0(&self, span: Span, body: P<ast::Expr>) -> P<ast::Expr> {
self.lambda(span, Vec::new(), body)
}
pub fn lambda1(&self, span: Span, body: P<ast::Expr>, ident: Ident) -> P<ast::Expr> {
self.lambda(span, vec![ident], body)
}
pub fn lambda_stmts_1(&self, span: Span, stmts: Vec<ast::Stmt>, ident: Ident) -> P<ast::Expr> {
self.lambda1(span, self.expr_block(self.block(span, stmts)), ident)
}
pub fn param(&self, span: Span, ident: Ident, ty: P<ast::Ty>) -> ast::Param {
let arg_pat = self.pat_ident(span, ident);
ast::Param {
attrs: AttrVec::default(),
id: ast::DUMMY_NODE_ID,
pat: arg_pat,
span,
ty,
is_placeholder: false,
}
}
// `self` is unused but keep it as method for the convenience use.
pub fn fn_decl(&self, inputs: Vec<ast::Param>, output: ast::FnRetTy) -> P<ast::FnDecl> {
P(ast::FnDecl { inputs, output })
}
pub fn item(
&self,
span: Span,
name: Ident,
attrs: Vec<ast::Attribute>,
kind: ast::ItemKind,
) -> P<ast::Item> {
// FIXME: Would be nice if our generated code didn't violate
// Rust coding conventions
P(ast::Item {
ident: name,
attrs,
id: ast::DUMMY_NODE_ID,
kind,
vis: ast::Visibility {
span: span.shrink_to_lo(),
kind: ast::VisibilityKind::Inherited,
tokens: None,
},
span,
tokens: None,
})
}
pub fn item_static(
&self,
span: Span,
name: Ident,
ty: P<ast::Ty>,
mutbl: ast::Mutability,
expr: P<ast::Expr>,
) -> P<ast::Item> {
self.item(span, name, Vec::new(), ast::ItemKind::Static(ty, mutbl, Some(expr)))
}
pub fn item_const(
&self,
span: Span,
name: Ident,
ty: P<ast::Ty>,
expr: P<ast::Expr>,
) -> P<ast::Item> {
let def = ast::Defaultness::Final;
self.item(span, name, Vec::new(), ast::ItemKind::Const(def, ty, Some(expr)))
}
pub fn attribute(&self, mi: ast::MetaItem) -> ast::Attribute {
attr::mk_attr_outer(mi)
}
pub fn meta_word(&self, sp: Span, w: Symbol) -> ast::MetaItem {
attr::mk_word_item(Ident::new(w, sp))
}
}