bjoernager/rust
bjoernager/rust
1
Fork 0
Code Issues Pull requests Activity

Add let-else to AST

Browse source
This commit is contained in:
Cameron Steffen 2021-06-22 13:00:58 -05:00
parent 6f388bb369
commit 89d2600d01
10 changed files with 92 additions and 26 deletions
Download patch file Download diff file Expand all files Collapse all files

32
compiler/rustc_parse/src/parser/stmt.rs
View file

@ -11,8 +11,9 @@ use rustc_ast as ast;
use rustc_ast::ptr::P;
use rustc_ast::token::{self, TokenKind};
use rustc_ast::util::classify;
use rustc_ast::AstLike;
use rustc_ast::{AttrStyle, AttrVec, Attribute, MacCall, MacCallStmt, MacStmtStyle};
use rustc_ast::{
AstLike, AttrStyle, AttrVec, Attribute, LocalKind, MacCall, MacCallStmt, MacStmtStyle,
};
use rustc_ast::{Block, BlockCheckMode, Expr, ExprKind, Local, Stmt};
use rustc_ast::{StmtKind, DUMMY_NODE_ID};
use rustc_errors::{Applicability, PResult};
@ -292,8 +293,19 @@ impl<'a> Parser<'a> {
return Err(err);
}
};
let kind = match init {
None => LocalKind::Decl,
Some(init) => {
if self.eat_keyword(kw::Else) {
let els = self.parse_block()?;
LocalKind::InitElse(init, els)
} else {
LocalKind::Init(init)
}
}
};
let hi = if self.token == token::Semi { self.token.span } else { self.prev_token.span };
Ok(P(ast::Local { ty, pat, init, id: DUMMY_NODE_ID, span: lo.to(hi), attrs, tokens: None }))
Ok(P(ast::Local { ty, pat, kind, id: DUMMY_NODE_ID, span: lo.to(hi), attrs, tokens: None }))
}
/// Parses the RHS of a local variable declaration (e.g., `= 14;`).
@ -495,13 +507,13 @@ impl<'a> Parser<'a> {
StmtKind::Expr(_) | StmtKind::MacCall(_) => {}
StmtKind::Local(ref mut local) if let Err(e) = self.expect_semi() => {
// We might be at the `,` in `let x = foo<bar, baz>;`. Try to recover.
match &mut local.init {
Some(ref mut expr) => {
self.check_mistyped_turbofish_with_multiple_type_params(e, expr)?;
// We found `foo<bar, baz>`, have we fully recovered?
self.expect_semi()?;
}
None => return Err(e),
match &mut local.kind {
LocalKind::Init(expr) | LocalKind::InitElse(expr, _) => {
self.check_mistyped_turbofish_with_multiple_type_params(e, expr)?;
// We found `foo<bar, baz>`, have we fully recovered?
self.expect_semi()?;
}
LocalKind::Decl => return Err(e),
}
eat_semi = false;
}