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Formally implement let chains

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This commit is contained in:
Caio 2022-01-18 19:38:17 -03:00
parent 9ad5d82f82
commit 5f74ef4fb1
31 changed files with 536 additions and 340 deletions
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18
compiler/rustc_ast_lowering/src/expr.rs
View File

@ -392,14 +392,20 @@ impl<'hir> LoweringContext<'_, 'hir> {
// If `cond` kind is `let`, returns `let`. Otherwise, wraps and returns `cond`
// in a temporary block.
fn manage_let_cond(&mut self, cond: &'hir hir::Expr<'hir>) -> &'hir hir::Expr<'hir> {
match cond.kind {
hir::ExprKind::Let(..) => cond,
_ => {
let span_block =
self.mark_span_with_reason(DesugaringKind::CondTemporary, cond.span, None);
self.expr_drop_temps(span_block, cond, AttrVec::new())
fn has_let_expr<'hir>(expr: &'hir hir::Expr<'hir>) -> bool {
match expr.kind {
hir::ExprKind::Binary(_, lhs, rhs) => has_let_expr(lhs) || has_let_expr(rhs),
hir::ExprKind::Let(..) => true,
_ => false,
}
}
if has_let_expr(cond) {
cond
} else {
let reason = DesugaringKind::CondTemporary;
let span_block = self.mark_span_with_reason(reason, cond.span, None);
self.expr_drop_temps(span_block, cond, AttrVec::new())
}
}
// We desugar: `'label: while $cond $body` into:

6
compiler/rustc_ast_passes/src/feature_gate.rs
View File

@ -707,11 +707,7 @@ pub fn check_crate(krate: &ast::Crate, sess: &Session) {
"`if let` guards are experimental",
"you can write `if matches!(<expr>, <pattern>)` instead of `if let <pattern> = <expr>`"
);
gate_all!(
let_chains,
"`let` expressions in this position are experimental",
"you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`"
);
gate_all!(let_chains, "`let` expressions in this position are unstable");
gate_all!(
async_closure,
"async closures are unstable",

2
compiler/rustc_feature/src/active.rs
View File

@ -415,7 +415,7 @@ declare_features! (
// Allows setting the threshold for the `large_assignments` lint.
(active, large_assignments, "1.52.0", Some(83518), None),
/// Allows `if/while p && let q = r && ...` chains.
(incomplete, let_chains, "1.37.0", Some(53667), None),
(active, let_chains, "1.37.0", Some(53667), None),
/// Allows `let...else` statements.
(active, let_else, "1.56.0", Some(87335), None),
/// Allows `#[link(..., cfg(..))]`.

2
compiler/rustc_middle/src/thir.rs
View File

@ -213,7 +213,7 @@ pub struct Expr<'tcx> {
#[derive(Debug, HashStable)]
pub enum ExprKind<'tcx> {
/// `Scope`s are used to explicitely mark destruction scopes,
/// `Scope`s are used to explicitly mark destruction scopes,
/// and to track the `HirId` of the expressions within the scope.
Scope {
region_scope: region::Scope,

16
compiler/rustc_mir_build/src/build/expr/into.rs
View File

@ -90,17 +90,8 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
};
let join_block = this.cfg.start_new_block();
this.cfg.terminate(
then_blk,
source_info,
TerminatorKind::Goto { target: join_block },
);
this.cfg.terminate(
else_blk,
source_info,
TerminatorKind::Goto { target: join_block },
);
this.cfg.goto(then_blk, source_info, join_block);
this.cfg.goto(else_blk, source_info, join_block);
join_block.unit()
}
ExprKind::Let { expr, ref pat } => {
@ -109,8 +100,6 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
this.lower_let_expr(block, &this.thir[expr], pat, scope, expr_span)
});
let join_block = this.cfg.start_new_block();
this.cfg.push_assign_constant(
true_block,
source_info,
@ -133,6 +122,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
},
);
let join_block = this.cfg.start_new_block();
this.cfg.goto(true_block, source_info, join_block);
this.cfg.goto(false_block, source_info, join_block);
join_block.unit()

19
compiler/rustc_mir_build/src/build/matches/mod.rs
View File

@ -47,6 +47,25 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
let expr_span = expr.span;
match expr.kind {
ExprKind::LogicalOp { op: LogicalOp::And, lhs, rhs } => {
let lhs_then_block = unpack!(this.then_else_break(
block,
&this.thir[lhs],
temp_scope_override,
break_scope,
variable_scope_span,
));
let rhs_then_block = unpack!(this.then_else_break(
lhs_then_block,
&this.thir[rhs],
temp_scope_override,
break_scope,
variable_scope_span,
));
rhs_then_block.unit()
}
ExprKind::Scope { region_scope, lint_level, value } => {
let region_scope = (region_scope, this.source_info(expr_span));
this.in_scope(region_scope, lint_level, |this| {

2
compiler/rustc_mir_build/src/build/scope.rs
View File

@ -498,7 +498,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
///
/// if let Some(x) = a && let Some(y) = b && let Some(z) = c { ... }
///
/// there are three possible ways the condition can be false and we may have
/// There are three possible ways the condition can be false and we may have
/// to drop `x`, `x` and `y`, or neither depending on which binding fails.
/// To handle this correctly we use a `DropTree` in a similar way to a
/// `loop` expression and 'break' out on all of the 'else' paths.

1
compiler/rustc_mir_build/src/thir/cx/expr.rs
View File

@ -315,7 +315,6 @@ impl<'tcx> Cx<'tcx> {
lhs: self.mirror_expr(lhs),
rhs: self.mirror_expr(rhs),
},
_ => {
let op = bin_op(op.node);
ExprKind::Binary {

43
compiler/rustc_mir_build/src/thir/pattern/check_match.rs
View File

@ -17,6 +17,7 @@ use rustc_session::lint::builtin::{
BINDINGS_WITH_VARIANT_NAME, IRREFUTABLE_LET_PATTERNS, UNREACHABLE_PATTERNS,
};
use rustc_session::Session;
use rustc_span::source_map::Spanned;
use rustc_span::{DesugaringKind, ExpnKind, Span};
crate fn check_match(tcx: TyCtxt<'_>, def_id: DefId) {
@ -445,6 +446,10 @@ fn check_let_reachability<'p, 'tcx>(
pat: &'p DeconstructedPat<'p, 'tcx>,
span: Span,
) {
if is_let_chain(cx.tcx, pat_id) {
return;
}
let arms = [MatchArm { pat, hir_id: pat_id, has_guard: false }];
let report = compute_match_usefulness(&cx, &arms, pat_id, pat.ty());
@ -764,8 +769,11 @@ pub enum LetSource {
fn let_source(tcx: TyCtxt<'_>, pat_id: HirId) -> LetSource {
let hir = tcx.hir();
let parent = hir.get_parent_node(pat_id);
match hir.get(parent) {
let parent_node = hir.get(parent);
match parent_node {
hir::Node::Arm(hir::Arm {
guard: Some(hir::Guard::IfLet(&hir::Pat { hir_id, .. }, _)),
..
@ -780,6 +788,7 @@ fn let_source(tcx: TyCtxt<'_>, pat_id: HirId) -> LetSource {
}
_ => {}
}
let parent_parent = hir.get_parent_node(parent);
let parent_parent_node = hir.get(parent_parent);
@ -792,12 +801,30 @@ fn let_source(tcx: TyCtxt<'_>, pat_id: HirId) -> LetSource {
..
}) = parent_parent_parent_parent_node
{
LetSource::WhileLet
} else if let hir::Node::Expr(hir::Expr { kind: hir::ExprKind::If { .. }, .. }) =
parent_parent_node
{
LetSource::IfLet
} else {
LetSource::GenericLet
return LetSource::WhileLet;
}
if let hir::Node::Expr(hir::Expr { kind: hir::ExprKind::If(..), .. }) = parent_parent_node {
return LetSource::IfLet;
}
LetSource::GenericLet
}
// Since this function is called within a let context, it is reasonable to assume that any parent
// `&&` infers a let chain
fn is_let_chain(tcx: TyCtxt<'_>, pat_id: HirId) -> bool {
let hir = tcx.hir();
let parent = hir.get_parent_node(pat_id);
let parent_parent = hir.get_parent_node(parent);
matches!(
hir.get(parent_parent),
hir::Node::Expr(
hir::Expr {
kind: hir::ExprKind::Binary(Spanned { node: hir::BinOpKind::And, .. }, ..),
..
},
..
)
)
}

2
src/test/ui/expr/if/attrs/let-chains-attr.rs
View File

@ -1,6 +1,6 @@
// check-pass
#![feature(let_chains)] //~ WARN the feature `let_chains` is incomplete
#![feature(let_chains)]
#[cfg(FALSE)]
fn foo() {

11
src/test/ui/expr/if/attrs/let-chains-attr.stderr
View File

@ -1,11 +0,0 @@
warning: the feature `let_chains` is incomplete and may not be safe to use and/or cause compiler crashes
--> $DIR/let-chains-attr.rs:3:12
|
LL | #![feature(let_chains)]
| ^^^^^^^^^^
|
= note: `#[warn(incomplete_features)]` on by default
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
warning: 1 warning emitted

93
src/test/ui/mir/mir_let_chains_drop_order.rs Normal file
View File

@ -0,0 +1,93 @@
// run-pass
// needs-unwind
// ignore-wasm32-bare compiled with panic=abort by default
// See `mir_drop_order.rs` for more information
#![feature(let_chains)]
use std::cell::RefCell;
use std::panic;
pub struct DropLogger<'a, T> {
extra: T,
id: usize,
log: &'a panic::AssertUnwindSafe<RefCell<Vec<usize>>>
}
impl<'a, T> Drop for DropLogger<'a, T> {
fn drop(&mut self) {
self.log.0.borrow_mut().push(self.id);
}
}
struct InjectedFailure;
#[allow(unreachable_code)]
fn main() {
let log = panic::AssertUnwindSafe(RefCell::new(vec![]));
let d = |id, extra| DropLogger { extra, id: id, log: &log };
let get = || -> Vec<_> {
let mut m = log.0.borrow_mut();
let n = m.drain(..);
n.collect()
};
{
let _x = (
d(
0,
d(
1,
if let Some(_) = d(2, Some(true)).extra && let DropLogger { .. } = d(3, None) {
None
} else {
Some(true)
}
).extra
),
d(4, None),
&d(5, None),
d(6, None),
if let DropLogger { .. } = d(7, None) && let DropLogger { .. } = d(8, None) {
d(9, None)
}
else {
// 10 is not constructed
d(10, None)
}
);
assert_eq!(get(), vec![3, 8, 7, 1, 2]);
}
assert_eq!(get(), vec![0, 4, 6, 9, 5]);
let _ = std::panic::catch_unwind(|| {
(
d(
11,
d(
12,
if let Some(_) = d(13, Some(true)).extra
&& let DropLogger { .. } = d(14, None)
{
None
} else {
Some(true)
}
).extra
),
d(15, None),
&d(16, None),
d(17, None),
if let DropLogger { .. } = d(18, None) && let DropLogger { .. } = d(19, None) {
d(20, None)
}
else {
// 10 is not constructed
d(21, None)
},
panic::panic_any(InjectedFailure)
);
});
assert_eq!(get(), vec![14, 19, 20, 17, 15, 11, 18, 16, 12, 13]);
}

9
src/test/ui/pattern/issue-82290.rs
View File

@ -1,9 +0,0 @@
// check-pass
#![feature(let_chains)] //~ WARN the feature `let_chains` is incomplete
fn main() {
if true && let x = 1 { //~ WARN irrefutable `let` pattern
let _ = x;
}
}

21
src/test/ui/pattern/issue-82290.stderr
View File

@ -1,21 +0,0 @@
warning: the feature `let_chains` is incomplete and may not be safe to use and/or cause compiler crashes
--> $DIR/issue-82290.rs:3:12
|
LL | #![feature(let_chains)]
| ^^^^^^^^^^
|
= note: `#[warn(incomplete_features)]` on by default
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
warning: irrefutable `let` pattern
--> $DIR/issue-82290.rs:6:16
|
LL | if true && let x = 1 {
| ^^^^^^^^^
|
= note: `#[warn(irrefutable_let_patterns)]` on by default
= note: this pattern will always match, so the `let` is useless
= help: consider removing `let`
warning: 2 warnings emitted

32
src/test/ui/rfc-2294-if-let-guard/feature-gate.rs
View File

@ -8,36 +8,36 @@ fn _if_let_guard() {
//~^ ERROR `if let` guards are experimental
() if (let 0 = 1) => {}
//~^ ERROR `let` expressions in this position are experimental
//~^ ERROR `let` expressions in this position are unstable
() if (((let 0 = 1))) => {}
//~^ ERROR `let` expressions in this position are experimental
//~^ ERROR `let` expressions in this position are unstable
() if true && let 0 = 1 => {}
//~^ ERROR `let` expressions in this position are experimental
//~^ ERROR `let` expressions in this position are unstable
() if let 0 = 1 && true => {}
//~^ ERROR `let` expressions in this position are experimental
//~^ ERROR `let` expressions in this position are unstable
() if (let 0 = 1) && true => {}
//~^ ERROR `let` expressions in this position are experimental
//~^ ERROR `let` expressions in this position are unstable
() if true && (let 0 = 1) => {}
//~^ ERROR `let` expressions in this position are experimental
//~^ ERROR `let` expressions in this position are unstable
() if (let 0 = 1) && (let 0 = 1) => {}
//~^ ERROR `let` expressions in this position are experimental
//~| ERROR `let` expressions in this position are experimental
//~^ ERROR `let` expressions in this position are unstable
//~| ERROR `let` expressions in this position are unstable
() if let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) => {}
//~^ ERROR `let` expressions in this position are experimental
//~| ERROR `let` expressions in this position are experimental
//~| ERROR `let` expressions in this position are experimental
//~| ERROR `let` expressions in this position are experimental
//~| ERROR `let` expressions in this position are experimental
//~^ ERROR `let` expressions in this position are unstable
//~| ERROR `let` expressions in this position are unstable
//~| ERROR `let` expressions in this position are unstable
//~| ERROR `let` expressions in this position are unstable
//~| ERROR `let` expressions in this position are unstable
() if let Range { start: _, end: _ } = (true..true) && false => {}
//~^ ERROR `let` expressions in this position are experimental
//~^ ERROR `let` expressions in this position are unstable
_ => {}
}
}
@ -52,9 +52,9 @@ fn _macros() {
}
}
use_expr!((let 0 = 1 && 0 == 0));
//~^ ERROR `let` expressions in this position are experimental
//~^ ERROR `let` expressions in this position are unstable
use_expr!((let 0 = 1));
//~^ ERROR `let` expressions in this position are experimental
//~^ ERROR `let` expressions in this position are unstable
match () {
#[cfg(FALSE)]
() if let 0 = 1 => {}

48
src/test/ui/rfc-2294-if-let-guard/feature-gate.stderr
View File

@ -27,7 +27,7 @@ LL | () if let 0 = 1 => {}
= help: add `#![feature(if_let_guard)]` to the crate attributes to enable
= help: you can write `if matches!(<expr>, <pattern>)` instead of `if let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:10:16
|
LL | () if (let 0 = 1) => {}
@ -35,9 +35,8 @@ LL | () if (let 0 = 1) => {}
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:13:18
|
LL | () if (((let 0 = 1))) => {}
@ -45,9 +44,8 @@ LL | () if (((let 0 = 1))) => {}
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:16:23
|
LL | () if true && let 0 = 1 => {}
@ -55,9 +53,8 @@ LL | () if true && let 0 = 1 => {}
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:19:15
|
LL | () if let 0 = 1 && true => {}
@ -65,9 +62,8 @@ LL | () if let 0 = 1 && true => {}
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:22:16
|
LL | () if (let 0 = 1) && true => {}
@ -75,9 +71,8 @@ LL | () if (let 0 = 1) && true => {}
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:25:24
|
LL | () if true && (let 0 = 1) => {}
@ -85,9 +80,8 @@ LL | () if true && (let 0 = 1) => {}
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:28:16
|
LL | () if (let 0 = 1) && (let 0 = 1) => {}
@ -95,9 +89,8 @@ LL | () if (let 0 = 1) && (let 0 = 1) => {}
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:28:31
|
LL | () if (let 0 = 1) && (let 0 = 1) => {}
@ -105,9 +98,8 @@ LL | () if (let 0 = 1) && (let 0 = 1) => {}
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:32:15
|
LL | () if let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) => {}
@ -115,9 +107,8 @@ LL | () if let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 =
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:32:28
|
LL | () if let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) => {}
@ -125,9 +116,8 @@ LL | () if let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 =
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:32:42
|
LL | () if let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) => {}
@ -135,9 +125,8 @@ LL | () if let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 =
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:32:55
|
LL | () if let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) => {}
@ -145,9 +134,8 @@ LL | () if let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 =
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:32:68
|
LL | () if let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) => {}
@ -155,9 +143,8 @@ LL | () if let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 =
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:39:15
|
LL | () if let Range { start: _, end: _ } = (true..true) && false => {}
@ -165,9 +152,8 @@ LL | () if let Range { start: _, end: _ } = (true..true) && false => {}
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:54:16
|
LL | use_expr!((let 0 = 1 && 0 == 0));
@ -175,9 +161,8 @@ LL | use_expr!((let 0 = 1 && 0 == 0));
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:56:16
|
LL | use_expr!((let 0 = 1));
@ -185,7 +170,6 @@ LL | use_expr!((let 0 = 1));
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error: aborting due to 19 previous errors

15
src/test/ui/rfc-2497-if-let-chains/ast-lowering-does-not-wrap-let-chains.rs Normal file
View File

@ -0,0 +1,15 @@
// run-pass
#![feature(let_chains)]
fn main() {
let first = Some(1);
let second = Some(2);
let mut n = 0;
if let x = first && let y = second && 1 == 1 {
assert_eq!(x, first);
assert_eq!(y, second);
n = 1;
}
assert_eq!(n, 1);
}

2
src/test/ui/rfc-2497-if-let-chains/ast-pretty-check.rs
View File

@ -1,4 +1,4 @@
// build-pass (FIXME(62277): could be check-pass?)
// check-pass
// compile-flags: -Z unpretty=expanded
fn main() {

2
src/test/ui/rfc-2497-if-let-chains/ast-pretty-check.stdout
View File

@ -4,7 +4,7 @@
use ::std::prelude::rust_2015::*;
#[macro_use]
extern crate std;
// build-pass (FIXME(62277): could be check-pass?)
// check-pass
// compile-flags: -Z unpretty=expanded
fn main() { if let 0 = 1 {} }

20
src/test/ui/rfc-2497-if-let-chains/chains-without-let.rs Normal file
View File

@ -0,0 +1,20 @@
fn and_chain() {
let z;
if true && { z = 3; true} && z == 3 {}
//~^ ERROR use of possibly-uninitialized
}
fn and_chain_2() {
let z;
true && { z = 3; true} && z == 3;
//~^ ERROR use of possibly-uninitialized
}
fn or_chain() {
let z;
if false || { z = 3; false} || z == 3 {}
//~^ ERROR use of possibly-uninitialized
}
fn main() {
}

21
src/test/ui/rfc-2497-if-let-chains/chains-without-let.stderr Normal file
View File

@ -0,0 +1,21 @@
error[E0381]: use of possibly-uninitialized variable: `z`
--> $DIR/chains-without-let.rs:3:34
|
LL | if true && { z = 3; true} && z == 3 {}
| ^ use of possibly-uninitialized `z`
error[E0381]: use of possibly-uninitialized variable: `z`
--> $DIR/chains-without-let.rs:9:31
|
LL | true && { z = 3; true} && z == 3;
| ^ use of possibly-uninitialized `z`
error[E0381]: use of possibly-uninitialized variable: `z`
--> $DIR/chains-without-let.rs:15:36
|
LL | if false || { z = 3; false} || z == 3 {}
| ^ use of possibly-uninitialized `z`
error: aborting due to 3 previous errors
For more information about this error, try `rustc --explain E0381`.

1
src/test/ui/rfc-2497-if-let-chains/disallowed-positions.rs
View File

@ -18,7 +18,6 @@
// To that end, we check some positions which is not part of the language above.
#![feature(let_chains)] // Avoid inflating `.stderr` with overzealous gates in this test.
//~^ WARN the feature `let_chains` is incomplete
#![allow(irrefutable_let_patterns)]

221
src/test/ui/rfc-2497-if-let-chains/disallowed-positions.stderr
View File

@ -1,5 +1,5 @@
error: expressions must be enclosed in braces to be used as const generic arguments
--> $DIR/disallowed-positions.rs:233:9
--> $DIR/disallowed-positions.rs:232:9
|
LL | true && let 1 = 1
| ^^^^^^^^^^^^^^^^^
@ -10,7 +10,7 @@ LL | { true && let 1 = 1 }
| + +
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:30:9
--> $DIR/disallowed-positions.rs:29:9
|
LL | if &let 0 = 0 {}
| ^^^^^^^^^
@ -19,7 +19,7 @@ LL | if &let 0 = 0 {}
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:33:9
--> $DIR/disallowed-positions.rs:32:9
|
LL | if !let 0 = 0 {}
| ^^^^^^^^^
@ -28,7 +28,7 @@ LL | if !let 0 = 0 {}
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:34:9
--> $DIR/disallowed-positions.rs:33:9
|
LL | if *let 0 = 0 {}
| ^^^^^^^^^
@ -37,7 +37,7 @@ LL | if *let 0 = 0 {}
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:36:9
--> $DIR/disallowed-positions.rs:35:9
|
LL | if -let 0 = 0 {}
| ^^^^^^^^^
@ -46,7 +46,7 @@ LL | if -let 0 = 0 {}
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:44:9
--> $DIR/disallowed-positions.rs:43:9
|
LL | if (let 0 = 0)? {}
| ^^^^^^^^^
@ -55,7 +55,7 @@ LL | if (let 0 = 0)? {}
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:48:16
--> $DIR/disallowed-positions.rs:47:16
|
LL | if true || let 0 = 0 {}
| ^^^^^^^^^
@ -64,7 +64,7 @@ LL | if true || let 0 = 0 {}
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:49:17
--> $DIR/disallowed-positions.rs:48:17
|
LL | if (true || let 0 = 0) {}
| ^^^^^^^^^
@ -73,7 +73,7 @@ LL | if (true || let 0 = 0) {}
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:50:25
--> $DIR/disallowed-positions.rs:49:25
|
LL | if true && (true || let 0 = 0) {}
| ^^^^^^^^^
@ -82,7 +82,7 @@ LL | if true && (true || let 0 = 0) {}
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:51:25
--> $DIR/disallowed-positions.rs:50:25
|
LL | if true || (true && let 0 = 0) {}
| ^^^^^^^^^
@ -91,7 +91,7 @@ LL | if true || (true && let 0 = 0) {}
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:54:12
--> $DIR/disallowed-positions.rs:53:12
|
LL | if x = let 0 = 0 {}
| ^^^^^^^^^
@ -100,7 +100,7 @@ LL | if x = let 0 = 0 {}
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:57:15
--> $DIR/disallowed-positions.rs:56:15
|
LL | if true..(let 0 = 0) {}
| ^^^^^^^^^
@ -109,7 +109,7 @@ LL | if true..(let 0 = 0) {}
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:59:11
--> $DIR/disallowed-positions.rs:58:11
|
LL | if ..(let 0 = 0) {}
| ^^^^^^^^^
@ -118,7 +118,7 @@ LL | if ..(let 0 = 0) {}
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:61:9
--> $DIR/disallowed-positions.rs:60:9
|
LL | if (let 0 = 0).. {}
| ^^^^^^^^^
@ -127,7 +127,7 @@ LL | if (let 0 = 0).. {}
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:65:8
--> $DIR/disallowed-positions.rs:64:8
|
LL | if let Range { start: _, end: _ } = true..true && false {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@ -136,7 +136,7 @@ LL | if let Range { start: _, end: _ } = true..true && false {}
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:69:8
--> $DIR/disallowed-positions.rs:68:8
|
LL | if let Range { start: _, end: _ } = true..true || false {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@ -145,7 +145,7 @@ LL | if let Range { start: _, end: _ } = true..true || false {}
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:76:8
--> $DIR/disallowed-positions.rs:75:8
|
LL | if let Range { start: F, end } = F..|| true {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@ -154,7 +154,7 @@ LL | if let Range { start: F, end } = F..|| true {}
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:84:8
--> $DIR/disallowed-positions.rs:83:8
|
LL | if let Range { start: true, end } = t..&&false {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@ -163,7 +163,7 @@ LL | if let Range { start: true, end } = t..&&false {}
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:90:19
--> $DIR/disallowed-positions.rs:89:19
|
LL | if let true = let true = true {}
| ^^^^^^^^^^^^^^^
@ -172,7 +172,7 @@ LL | if let true = let true = true {}
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:94:12
--> $DIR/disallowed-positions.rs:93:12
|
LL | while &let 0 = 0 {}
| ^^^^^^^^^
@ -181,7 +181,7 @@ LL | while &let 0 = 0 {}
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:97:12
--> $DIR/disallowed-positions.rs:96:12
|
LL | while !let 0 = 0 {}
| ^^^^^^^^^
@ -190,7 +190,7 @@ LL | while !let 0 = 0 {}
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:98:12
--> $DIR/disallowed-positions.rs:97:12
|
LL | while *let 0 = 0 {}
| ^^^^^^^^^
@ -199,7 +199,7 @@ LL | while *let 0 = 0 {}
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:100:12
--> $DIR/disallowed-positions.rs:99:12
|
LL | while -let 0 = 0 {}
| ^^^^^^^^^
@ -208,7 +208,7 @@ LL | while -let 0 = 0 {}
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:108:12
--> $DIR/disallowed-positions.rs:107:12
|
LL | while (let 0 = 0)? {}
| ^^^^^^^^^
@ -217,7 +217,7 @@ LL | while (let 0 = 0)? {}
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:112:19
--> $DIR/disallowed-positions.rs:111:19
|
LL | while true || let 0 = 0 {}
| ^^^^^^^^^
@ -226,7 +226,7 @@ LL | while true || let 0 = 0 {}
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:113:20
--> $DIR/disallowed-positions.rs:112:20
|
LL | while (true || let 0 = 0) {}
| ^^^^^^^^^
@ -235,7 +235,7 @@ LL | while (true || let 0 = 0) {}
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:114:28
--> $DIR/disallowed-positions.rs:113:28
|
LL | while true && (true || let 0 = 0) {}
| ^^^^^^^^^
@ -244,7 +244,7 @@ LL | while true && (true || let 0 = 0) {}
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:115:28
--> $DIR/disallowed-positions.rs:114:28
|
LL | while true || (true && let 0 = 0) {}
| ^^^^^^^^^
@ -253,7 +253,7 @@ LL | while true || (true && let 0 = 0) {}
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:118:15
--> $DIR/disallowed-positions.rs:117:15
|
LL | while x = let 0 = 0 {}
| ^^^^^^^^^
@ -262,7 +262,7 @@ LL | while x = let 0 = 0 {}
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:121:18
--> $DIR/disallowed-positions.rs:120:18
|
LL | while true..(let 0 = 0) {}
| ^^^^^^^^^
@ -271,7 +271,7 @@ LL | while true..(let 0 = 0) {}
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:123:14
--> $DIR/disallowed-positions.rs:122:14
|
LL | while ..(let 0 = 0) {}
| ^^^^^^^^^
@ -280,7 +280,7 @@ LL | while ..(let 0 = 0) {}
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:125:12
--> $DIR/disallowed-positions.rs:124:12
|
LL | while (let 0 = 0).. {}
| ^^^^^^^^^
@ -289,7 +289,7 @@ LL | while (let 0 = 0).. {}
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:129:11
--> $DIR/disallowed-positions.rs:128:11
|
LL | while let Range { start: _, end: _ } = true..true && false {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@ -298,7 +298,7 @@ LL | while let Range { start: _, end: _ } = true..true && false {}
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:133:11
--> $DIR/disallowed-positions.rs:132:11
|
LL | while let Range { start: _, end: _ } = true..true || false {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@ -307,7 +307,7 @@ LL | while let Range { start: _, end: _ } = true..true || false {}
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:140:11
--> $DIR/disallowed-positions.rs:139:11
|
LL | while let Range { start: F, end } = F..|| true {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@ -316,7 +316,7 @@ LL | while let Range { start: F, end } = F..|| true {}
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:148:11
--> $DIR/disallowed-positions.rs:147:11
|
LL | while let Range { start: true, end } = t..&&false {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@ -325,7 +325,7 @@ LL | while let Range { start: true, end } = t..&&false {}
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:154:22
--> $DIR/disallowed-positions.rs:153:22
|
LL | while let true = let true = true {}
| ^^^^^^^^^^^^^^^
@ -334,7 +334,7 @@ LL | while let true = let true = true {}
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:168:6
--> $DIR/disallowed-positions.rs:167:6
|
LL | &let 0 = 0;
| ^^^^^^^^^
@ -343,7 +343,7 @@ LL | &let 0 = 0;
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:170:6
--> $DIR/disallowed-positions.rs:169:6
|
LL | !let 0 = 0;
| ^^^^^^^^^
@ -352,7 +352,7 @@ LL | !let 0 = 0;
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:171:6
--> $DIR/disallowed-positions.rs:170:6
|
LL | *let 0 = 0;
| ^^^^^^^^^
@ -361,7 +361,7 @@ LL | *let 0 = 0;
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:173:6
--> $DIR/disallowed-positions.rs:172:6
|
LL | -let 0 = 0;
| ^^^^^^^^^
@ -370,7 +370,7 @@ LL | -let 0 = 0;
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:181:6
--> $DIR/disallowed-positions.rs:180:6
|
LL | (let 0 = 0)?;
| ^^^^^^^^^
@ -379,7 +379,7 @@ LL | (let 0 = 0)?;
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:185:13
--> $DIR/disallowed-positions.rs:184:13
|
LL | true || let 0 = 0;
| ^^^^^^^^^
@ -388,7 +388,7 @@ LL | true || let 0 = 0;
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:186:14
--> $DIR/disallowed-positions.rs:185:14
|
LL | (true || let 0 = 0);
| ^^^^^^^^^
@ -397,7 +397,7 @@ LL | (true || let 0 = 0);
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:187:22
--> $DIR/disallowed-positions.rs:186:22
|
LL | true && (true || let 0 = 0);
| ^^^^^^^^^
@ -406,7 +406,7 @@ LL | true && (true || let 0 = 0);
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:190:9
--> $DIR/disallowed-positions.rs:189:9
|
LL | x = let 0 = 0;
| ^^^^^^^^^
@ -415,7 +415,7 @@ LL | x = let 0 = 0;
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:192:12
--> $DIR/disallowed-positions.rs:191:12
|
LL | true..(let 0 = 0);
| ^^^^^^^^^
@ -424,7 +424,7 @@ LL | true..(let 0 = 0);
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:193:8
--> $DIR/disallowed-positions.rs:192:8
|
LL | ..(let 0 = 0);
| ^^^^^^^^^
@ -433,7 +433,7 @@ LL | ..(let 0 = 0);
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:194:6
--> $DIR/disallowed-positions.rs:193:6
|
LL | (let 0 = 0)..;
| ^^^^^^^^^
@ -442,7 +442,7 @@ LL | (let 0 = 0)..;
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:196:6
--> $DIR/disallowed-positions.rs:195:6
|
LL | (let Range { start: _, end: _ } = true..true || false);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@ -451,7 +451,7 @@ LL | (let Range { start: _, end: _ } = true..true || false);
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:200:6
--> $DIR/disallowed-positions.rs:199:6
|
LL | (let true = let true = true);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^
@ -460,7 +460,7 @@ LL | (let true = let true = true);
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:204:6
--> $DIR/disallowed-positions.rs:203:6
|
LL | &let 0 = 0
| ^^^^^^^^^
@ -469,7 +469,7 @@ LL | &let 0 = 0
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:215:17
--> $DIR/disallowed-positions.rs:214:17
|
LL | true && let 1 = 1
| ^^^^^^^^^
@ -478,7 +478,7 @@ LL | true && let 1 = 1
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:219:17
--> $DIR/disallowed-positions.rs:218:17
|
LL | true && let 1 = 1
| ^^^^^^^^^
@ -487,7 +487,7 @@ LL | true && let 1 = 1
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:223:17
--> $DIR/disallowed-positions.rs:222:17
|
LL | true && let 1 = 1
| ^^^^^^^^^
@ -496,7 +496,7 @@ LL | true && let 1 = 1
= note: as well as when nested within `&&` and parentheses in those conditions
error: `let` expressions are not supported here
--> $DIR/disallowed-positions.rs:233:17
--> $DIR/disallowed-positions.rs:232:17
|
LL | true && let 1 = 1
| ^^^^^^^^^
@ -504,17 +504,8 @@ LL | true && let 1 = 1
= note: only supported directly in conditions of `if`- and `while`-expressions
= note: as well as when nested within `&&` and parentheses in those conditions
warning: the feature `let_chains` is incomplete and may not be safe to use and/or cause compiler crashes
--> $DIR/disallowed-positions.rs:20:12
|
LL | #![feature(let_chains)] // Avoid inflating `.stderr` with overzealous gates in this test.
| ^^^^^^^^^^
|
= note: `#[warn(incomplete_features)]` on by default
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
error[E0308]: mismatched types
--> $DIR/disallowed-positions.rs:30:8
--> $DIR/disallowed-positions.rs:29:8
|
LL | if &let 0 = 0 {}
| ^^^^^^^^^^ expected `bool`, found `&bool`
@ -526,19 +517,19 @@ LL + if let 0 = 0 {}
|
error[E0614]: type `bool` cannot be dereferenced
--> $DIR/disallowed-positions.rs:34:8
--> $DIR/disallowed-positions.rs:33:8
|
LL | if *let 0 = 0 {}
| ^^^^^^^^^^
error[E0600]: cannot apply unary operator `-` to type `bool`
--> $DIR/disallowed-positions.rs:36:8
--> $DIR/disallowed-positions.rs:35:8
|
LL | if -let 0 = 0 {}
| ^^^^^^^^^^ cannot apply unary operator `-`
error[E0277]: the `?` operator can only be applied to values that implement `Try`
--> $DIR/disallowed-positions.rs:44:8
--> $DIR/disallowed-positions.rs:43:8
|
LL | if (let 0 = 0)? {}
| ^^^^^^^^^^^^ the `?` operator cannot be applied to type `bool`
@ -546,7 +537,7 @@ LL | if (let 0 = 0)? {}
= help: the trait `Try` is not implemented for `bool`
error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `FromResidual`)
--> $DIR/disallowed-positions.rs:44:19
--> $DIR/disallowed-positions.rs:43:19
|
LL | / fn nested_within_if_expr() {
LL | | if &let 0 = 0 {}
@ -563,7 +554,7 @@ LL | | }
= help: the trait `FromResidual<_>` is not implemented for `()`
error[E0308]: mismatched types
--> $DIR/disallowed-positions.rs:54:8
--> $DIR/disallowed-positions.rs:53:8
|
LL | if x = let 0 = 0 {}
| ^^^^^^^^^^^^^ expected `bool`, found `()`
@ -574,7 +565,7 @@ LL | if x == let 0 = 0 {}
| ~~
error[E0308]: mismatched types
--> $DIR/disallowed-positions.rs:57:8
--> $DIR/disallowed-positions.rs:56:8
|
LL | if true..(let 0 = 0) {}
| ^^^^^^^^^^^^^^^^^ expected `bool`, found struct `std::ops::Range`
@ -583,7 +574,7 @@ LL | if true..(let 0 = 0) {}
found struct `std::ops::Range<bool>`
error[E0308]: mismatched types
--> $DIR/disallowed-positions.rs:59:8
--> $DIR/disallowed-positions.rs:58:8
|
LL | if ..(let 0 = 0) {}
| ^^^^^^^^^^^^^ expected `bool`, found struct `RangeTo`
@ -592,7 +583,7 @@ LL | if ..(let 0 = 0) {}
found struct `RangeTo<bool>`
error[E0308]: mismatched types
--> $DIR/disallowed-positions.rs:61:8
--> $DIR/disallowed-positions.rs:60:8
|
LL | if (let 0 = 0).. {}
| ^^^^^^^^^^^^^ expected `bool`, found struct `RangeFrom`
@ -601,7 +592,7 @@ LL | if (let 0 = 0).. {}
found struct `RangeFrom<bool>`
error[E0308]: mismatched types
--> $DIR/disallowed-positions.rs:65:12
--> $DIR/disallowed-positions.rs:64:12
|
LL | if let Range { start: _, end: _ } = true..true && false {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^ ---- this expression has type `bool`
@ -612,7 +603,7 @@ LL | if let Range { start: _, end: _ } = true..true && false {}
found struct `std::ops::Range<_>`
error[E0308]: mismatched types
--> $DIR/disallowed-positions.rs:65:8
--> $DIR/disallowed-positions.rs:64:8
|
LL | if let Range { start: _, end: _ } = true..true && false {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `bool`, found struct `std::ops::Range`
@ -621,7 +612,7 @@ LL | if let Range { start: _, end: _ } = true..true && false {}
found struct `std::ops::Range<bool>`
error[E0308]: mismatched types
--> $DIR/disallowed-positions.rs:69:12
--> $DIR/disallowed-positions.rs:68:12
|
LL | if let Range { start: _, end: _ } = true..true || false {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^ ---- this expression has type `bool`
@ -632,7 +623,7 @@ LL | if let Range { start: _, end: _ } = true..true || false {}
found struct `std::ops::Range<_>`
error[E0308]: mismatched types
--> $DIR/disallowed-positions.rs:69:8
--> $DIR/disallowed-positions.rs:68:8
|
LL | if let Range { start: _, end: _ } = true..true || false {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `bool`, found struct `std::ops::Range`
@ -641,7 +632,7 @@ LL | if let Range { start: _, end: _ } = true..true || false {}
found struct `std::ops::Range<bool>`
error[E0308]: mismatched types
--> $DIR/disallowed-positions.rs:76:12
--> $DIR/disallowed-positions.rs:75:12
|
LL | if let Range { start: F, end } = F..|| true {}
| ^^^^^^^^^^^^^^^^^^^^^^^ - this expression has type `fn() -> bool`
@ -652,16 +643,16 @@ LL | if let Range { start: F, end } = F..|| true {}
found struct `std::ops::Range<_>`
error[E0308]: mismatched types
--> $DIR/disallowed-positions.rs:76:41
--> $DIR/disallowed-positions.rs:75:41
|
LL | if let Range { start: F, end } = F..|| true {}
| ^^^^^^^ expected `bool`, found closure
|
= note: expected type `bool`
found closure `[closure@$DIR/disallowed-positions.rs:76:41: 76:48]`
found closure `[closure@$DIR/disallowed-positions.rs:75:41: 75:48]`
error[E0308]: mismatched types
--> $DIR/disallowed-positions.rs:76:8
--> $DIR/disallowed-positions.rs:75:8
|
LL | if let Range { start: F, end } = F..|| true {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `bool`, found struct `std::ops::Range`
@ -670,7 +661,7 @@ LL | if let Range { start: F, end } = F..|| true {}
found struct `std::ops::Range<bool>`
error[E0308]: mismatched types
--> $DIR/disallowed-positions.rs:84:12
--> $DIR/disallowed-positions.rs:83:12
|
LL | if let Range { start: true, end } = t..&&false {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^ - this expression has type `&&bool`
@ -681,13 +672,13 @@ LL | if let Range { start: true, end } = t..&&false {}
found struct `std::ops::Range<_>`
error[E0308]: mismatched types
--> $DIR/disallowed-positions.rs:84:44
--> $DIR/disallowed-positions.rs:83:44
|
LL | if let Range { start: true, end } = t..&&false {}
| ^^^^^^^ expected `bool`, found `&&bool`
error[E0308]: mismatched types
--> $DIR/disallowed-positions.rs:84:8
--> $DIR/disallowed-positions.rs:83:8
|
LL | if let Range { start: true, end } = t..&&false {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `bool`, found struct `std::ops::Range`
@ -696,7 +687,7 @@ LL | if let Range { start: true, end } = t..&&false {}
found struct `std::ops::Range<bool>`
error[E0277]: the `?` operator can only be applied to values that implement `Try`
--> $DIR/disallowed-positions.rs:40:20
--> $DIR/disallowed-positions.rs:39:20
|
LL | if let 0 = 0? {}
| ^^ the `?` operator cannot be applied to type `{integer}`
@ -704,7 +695,7 @@ LL | if let 0 = 0? {}
= help: the trait `Try` is not implemented for `{integer}`
error[E0308]: mismatched types
--> $DIR/disallowed-positions.rs:94:11
--> $DIR/disallowed-positions.rs:93:11
|
LL | while &let 0 = 0 {}
| ^^^^^^^^^^ expected `bool`, found `&bool`
@ -716,19 +707,19 @@ LL + while let 0 = 0 {}
|
error[E0614]: type `bool` cannot be dereferenced
--> $DIR/disallowed-positions.rs:98:11
--> $DIR/disallowed-positions.rs:97:11
|
LL | while *let 0 = 0 {}
| ^^^^^^^^^^
error[E0600]: cannot apply unary operator `-` to type `bool`
--> $DIR/disallowed-positions.rs:100:11
--> $DIR/disallowed-positions.rs:99:11
|
LL | while -let 0 = 0 {}
| ^^^^^^^^^^ cannot apply unary operator `-`
error[E0277]: the `?` operator can only be applied to values that implement `Try`
--> $DIR/disallowed-positions.rs:108:11
--> $DIR/disallowed-positions.rs:107:11
|
LL | while (let 0 = 0)? {}
| ^^^^^^^^^^^^ the `?` operator cannot be applied to type `bool`
@ -736,7 +727,7 @@ LL | while (let 0 = 0)? {}
= help: the trait `Try` is not implemented for `bool`
error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `FromResidual`)
--> $DIR/disallowed-positions.rs:108:22
--> $DIR/disallowed-positions.rs:107:22
|
LL | / fn nested_within_while_expr() {
LL | | while &let 0 = 0 {}
@ -753,7 +744,7 @@ LL | | }
= help: the trait `FromResidual<_>` is not implemented for `()`
error[E0308]: mismatched types
--> $DIR/disallowed-positions.rs:118:11
--> $DIR/disallowed-positions.rs:117:11
|
LL | while x = let 0 = 0 {}
| ^^^^^^^^^^^^^ expected `bool`, found `()`
@ -764,7 +755,7 @@ LL | while x == let 0 = 0 {}
| ~~
error[E0308]: mismatched types
--> $DIR/disallowed-positions.rs:121:11
--> $DIR/disallowed-positions.rs:120:11
|
LL | while true..(let 0 = 0) {}
| ^^^^^^^^^^^^^^^^^ expected `bool`, found struct `std::ops::Range`
@ -773,7 +764,7 @@ LL | while true..(let 0 = 0) {}
found struct `std::ops::Range<bool>`
error[E0308]: mismatched types
--> $DIR/disallowed-positions.rs:123:11
--> $DIR/disallowed-positions.rs:122:11
|
LL | while ..(let 0 = 0) {}
| ^^^^^^^^^^^^^ expected `bool`, found struct `RangeTo`
@ -782,7 +773,7 @@ LL | while ..(let 0 = 0) {}
found struct `RangeTo<bool>`
error[E0308]: mismatched types
--> $DIR/disallowed-positions.rs:125:11
--> $DIR/disallowed-positions.rs:124:11
|
LL | while (let 0 = 0).. {}
| ^^^^^^^^^^^^^ expected `bool`, found struct `RangeFrom`
@ -791,7 +782,7 @@ LL | while (let 0 = 0).. {}
found struct `RangeFrom<bool>`
error[E0308]: mismatched types
--> $DIR/disallowed-positions.rs:129:15
--> $DIR/disallowed-positions.rs:128:15
|
LL | while let Range { start: _, end: _ } = true..true && false {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^ ---- this expression has type `bool`
@ -802,7 +793,7 @@ LL | while let Range { start: _, end: _ } = true..true && false {}
found struct `std::ops::Range<_>`
error[E0308]: mismatched types
--> $DIR/disallowed-positions.rs:129:11
--> $DIR/disallowed-positions.rs:128:11
|
LL | while let Range { start: _, end: _ } = true..true && false {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `bool`, found struct `std::ops::Range`
@ -811,7 +802,7 @@ LL | while let Range { start: _, end: _ } = true..true && false {}
found struct `std::ops::Range<bool>`
error[E0308]: mismatched types
--> $DIR/disallowed-positions.rs:133:15
--> $DIR/disallowed-positions.rs:132:15
|
LL | while let Range { start: _, end: _ } = true..true || false {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^ ---- this expression has type `bool`
@ -822,7 +813,7 @@ LL | while let Range { start: _, end: _ } = true..true || false {}
found struct `std::ops::Range<_>`
error[E0308]: mismatched types
--> $DIR/disallowed-positions.rs:133:11
--> $DIR/disallowed-positions.rs:132:11
|
LL | while let Range { start: _, end: _ } = true..true || false {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `bool`, found struct `std::ops::Range`
@ -831,7 +822,7 @@ LL | while let Range { start: _, end: _ } = true..true || false {}
found struct `std::ops::Range<bool>`
error[E0308]: mismatched types
--> $DIR/disallowed-positions.rs:140:15
--> $DIR/disallowed-positions.rs:139:15
|
LL | while let Range { start: F, end } = F..|| true {}
| ^^^^^^^^^^^^^^^^^^^^^^^ - this expression has type `fn() -> bool`
@ -842,16 +833,16 @@ LL | while let Range { start: F, end } = F..|| true {}
found struct `std::ops::Range<_>`
error[E0308]: mismatched types
--> $DIR/disallowed-positions.rs:140:44
--> $DIR/disallowed-positions.rs:139:44
|
LL | while let Range { start: F, end } = F..|| true {}
| ^^^^^^^ expected `bool`, found closure
|
= note: expected type `bool`
found closure `[closure@$DIR/disallowed-positions.rs:140:44: 140:51]`
found closure `[closure@$DIR/disallowed-positions.rs:139:44: 139:51]`
error[E0308]: mismatched types
--> $DIR/disallowed-positions.rs:140:11
--> $DIR/disallowed-positions.rs:139:11
|
LL | while let Range { start: F, end } = F..|| true {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `bool`, found struct `std::ops::Range`
@ -860,7 +851,7 @@ LL | while let Range { start: F, end } = F..|| true {}
found struct `std::ops::Range<bool>`
error[E0308]: mismatched types
--> $DIR/disallowed-positions.rs:148:15
--> $DIR/disallowed-positions.rs:147:15
|
LL | while let Range { start: true, end } = t..&&false {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^ - this expression has type `&&bool`
@ -871,13 +862,13 @@ LL | while let Range { start: true, end } = t..&&false {}
found struct `std::ops::Range<_>`
error[E0308]: mismatched types
--> $DIR/disallowed-positions.rs:148:47
--> $DIR/disallowed-positions.rs:147:47
|
LL | while let Range { start: true, end } = t..&&false {}
| ^^^^^^^ expected `bool`, found `&&bool`
error[E0308]: mismatched types
--> $DIR/disallowed-positions.rs:148:11
--> $DIR/disallowed-positions.rs:147:11
|
LL | while let Range { start: true, end } = t..&&false {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `bool`, found struct `std::ops::Range`
@ -886,7 +877,7 @@ LL | while let Range { start: true, end } = t..&&false {}
found struct `std::ops::Range<bool>`
error[E0277]: the `?` operator can only be applied to values that implement `Try`
--> $DIR/disallowed-positions.rs:104:23
--> $DIR/disallowed-positions.rs:103:23
|
LL | while let 0 = 0? {}
| ^^ the `?` operator cannot be applied to type `{integer}`
@ -894,19 +885,19 @@ LL | while let 0 = 0? {}
= help: the trait `Try` is not implemented for `{integer}`
error[E0614]: type `bool` cannot be dereferenced
--> $DIR/disallowed-positions.rs:171:5
--> $DIR/disallowed-positions.rs:170:5
|
LL | *let 0 = 0;
| ^^^^^^^^^^
error[E0600]: cannot apply unary operator `-` to type `bool`
--> $DIR/disallowed-positions.rs:173:5
--> $DIR/disallowed-positions.rs:172:5
|
LL | -let 0 = 0;
| ^^^^^^^^^^ cannot apply unary operator `-`
error[E0277]: the `?` operator can only be applied to values that implement `Try`
--> $DIR/disallowed-positions.rs:181:5
--> $DIR/disallowed-positions.rs:180:5
|
LL | (let 0 = 0)?;
| ^^^^^^^^^^^^ the `?` operator cannot be applied to type `bool`
@ -914,7 +905,7 @@ LL | (let 0 = 0)?;
= help: the trait `Try` is not implemented for `bool`
error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `FromResidual`)
--> $DIR/disallowed-positions.rs:181:16
--> $DIR/disallowed-positions.rs:180:16
|
LL | / fn outside_if_and_while_expr() {
LL | | &let 0 = 0;
@ -931,7 +922,7 @@ LL | | }
= help: the trait `FromResidual<_>` is not implemented for `()`
error[E0308]: mismatched types
--> $DIR/disallowed-positions.rs:196:10
--> $DIR/disallowed-positions.rs:195:10
|
LL | (let Range { start: _, end: _ } = true..true || false);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^ ---- this expression has type `bool`
@ -942,7 +933,7 @@ LL | (let Range { start: _, end: _ } = true..true || false);
found struct `std::ops::Range<_>`
error[E0308]: mismatched types
--> $DIR/disallowed-positions.rs:204:5
--> $DIR/disallowed-positions.rs:203:5
|
LL | fn outside_if_and_while_expr() {
| - help: try adding a return type: `-> &bool`
@ -951,14 +942,14 @@ LL | &let 0 = 0
| ^^^^^^^^^^ expected `()`, found `&bool`
error[E0277]: the `?` operator can only be applied to values that implement `Try`
--> $DIR/disallowed-positions.rs:177:17
--> $DIR/disallowed-positions.rs:176:17
|
LL | let 0 = 0?;
| ^^ the `?` operator cannot be applied to type `{integer}`
|
= help: the trait `Try` is not implemented for `{integer}`
error: aborting due to 103 previous errors; 1 warning emitted
error: aborting due to 103 previous errors
Some errors have detailed explanations: E0277, E0308, E0600, E0614.
For more information about an error, try `rustc --explain E0277`.

64
src/test/ui/rfc-2497-if-let-chains/feature-gate.rs
View File

@ -12,79 +12,79 @@ fn _if() {
if let 0 = 1 {} // Stable!
if (let 0 = 1) {}
//~^ ERROR `let` expressions in this position are experimental [E0658]
//~^ ERROR `let` expressions in this position are unstable [E0658]
if (((let 0 = 1))) {}
//~^ ERROR `let` expressions in this position are experimental [E0658]
//~^ ERROR `let` expressions in this position are unstable [E0658]
if true && let 0 = 1 {}
//~^ ERROR `let` expressions in this position are experimental [E0658]
//~^ ERROR `let` expressions in this position are unstable [E0658]
if let 0 = 1 && true {}
//~^ ERROR `let` expressions in this position are experimental [E0658]
//~^ ERROR `let` expressions in this position are unstable [E0658]
if (let 0 = 1) && true {}
//~^ ERROR `let` expressions in this position are experimental [E0658]
//~^ ERROR `let` expressions in this position are unstable [E0658]
if true && (let 0 = 1) {}
//~^ ERROR `let` expressions in this position are experimental [E0658]
//~^ ERROR `let` expressions in this position are unstable [E0658]
if (let 0 = 1) && (let 0 = 1) {}
//~^ ERROR `let` expressions in this position are experimental [E0658]
//~| ERROR `let` expressions in this position are experimental [E0658]
//~^ ERROR `let` expressions in this position are unstable [E0658]
//~| ERROR `let` expressions in this position are unstable [E0658]
if let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) {}
//~^ ERROR `let` expressions in this position are experimental [E0658]
//~| ERROR `let` expressions in this position are experimental [E0658]
//~| ERROR `let` expressions in this position are experimental [E0658]
//~| ERROR `let` expressions in this position are experimental [E0658]
//~| ERROR `let` expressions in this position are experimental [E0658]
//~^ ERROR `let` expressions in this position are unstable [E0658]
//~| ERROR `let` expressions in this position are unstable [E0658]
//~| ERROR `let` expressions in this position are unstable [E0658]
//~| ERROR `let` expressions in this position are unstable [E0658]
//~| ERROR `let` expressions in this position are unstable [E0658]
if let Range { start: _, end: _ } = (true..true) && false {}
//~^ ERROR `let` expressions in this position are experimental [E0658]
//~^ ERROR `let` expressions in this position are unstable [E0658]
}
fn _while() {
while let 0 = 1 {} // Stable!
while (let 0 = 1) {}
//~^ ERROR `let` expressions in this position are experimental [E0658]
//~^ ERROR `let` expressions in this position are unstable [E0658]
while (((let 0 = 1))) {}
//~^ ERROR `let` expressions in this position are experimental [E0658]
//~^ ERROR `let` expressions in this position are unstable [E0658]
while true && let 0 = 1 {}
//~^ ERROR `let` expressions in this position are experimental [E0658]
//~^ ERROR `let` expressions in this position are unstable [E0658]
while let 0 = 1 && true {}
//~^ ERROR `let` expressions in this position are experimental [E0658]
//~^ ERROR `let` expressions in this position are unstable [E0658]
while (let 0 = 1) && true {}
//~^ ERROR `let` expressions in this position are experimental [E0658]
//~^ ERROR `let` expressions in this position are unstable [E0658]
while true && (let 0 = 1) {}
//~^ ERROR `let` expressions in this position are experimental [E0658]
//~^ ERROR `let` expressions in this position are unstable [E0658]
while (let 0 = 1) && (let 0 = 1) {}
//~^ ERROR `let` expressions in this position are experimental [E0658]
//~| ERROR `let` expressions in this position are experimental [E0658]
//~^ ERROR `let` expressions in this position are unstable [E0658]
//~| ERROR `let` expressions in this position are unstable [E0658]
while let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) {}
//~^ ERROR `let` expressions in this position are experimental [E0658]
//~| ERROR `let` expressions in this position are experimental [E0658]
//~| ERROR `let` expressions in this position are experimental [E0658]
//~| ERROR `let` expressions in this position are experimental [E0658]
//~| ERROR `let` expressions in this position are experimental [E0658]
//~^ ERROR `let` expressions in this position are unstable [E0658]
//~| ERROR `let` expressions in this position are unstable [E0658]
//~| ERROR `let` expressions in this position are unstable [E0658]
//~| ERROR `let` expressions in this position are unstable [E0658]
//~| ERROR `let` expressions in this position are unstable [E0658]
while let Range { start: _, end: _ } = (true..true) && false {}
//~^ ERROR `let` expressions in this position are experimental [E0658]
//~^ ERROR `let` expressions in this position are unstable [E0658]
}
fn _macros() {
macro_rules! noop_expr { ($e:expr) => {}; }
noop_expr!((let 0 = 1));
//~^ ERROR `let` expressions in this position are experimental [E0658]
//~^ ERROR `let` expressions in this position are unstable [E0658]
macro_rules! use_expr {
($e:expr) => {
@ -93,11 +93,11 @@ fn _macros() {
}
}
use_expr!((let 0 = 1 && 0 == 0));
//~^ ERROR `let` expressions in this position are experimental [E0658]
//~^ ERROR `let` expressions in this position are unstable [E0658]
use_expr!((let 0 = 1));
//~^ ERROR `let` expressions in this position are experimental [E0658]
//~^ ERROR `let` expressions in this position are unstable [E0658]
#[cfg(FALSE)] (let 0 = 1);
//~^ ERROR `let` expressions in this position are experimental [E0658]
//~^ ERROR `let` expressions in this position are unstable [E0658]
use_expr!(let 0 = 1);
//~^ ERROR no rules expected the token `let`
// ^--- FIXME(53667): Consider whether `Let` can be added to `ident_can_begin_expr`.

96
src/test/ui/rfc-2497-if-let-chains/feature-gate.stderr
View File

@ -7,7 +7,7 @@ LL | macro_rules! use_expr {
LL | use_expr!(let 0 = 1);
| ^^^ no rules expected this token in macro call
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:14:9
|
LL | if (let 0 = 1) {}
@ -15,9 +15,8 @@ LL | if (let 0 = 1) {}
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:17:11
|
LL | if (((let 0 = 1))) {}
@ -25,9 +24,8 @@ LL | if (((let 0 = 1))) {}
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:20:16
|
LL | if true && let 0 = 1 {}
@ -35,9 +33,8 @@ LL | if true && let 0 = 1 {}
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:23:8
|
LL | if let 0 = 1 && true {}
@ -45,9 +42,8 @@ LL | if let 0 = 1 && true {}
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:26:9
|
LL | if (let 0 = 1) && true {}
@ -55,9 +51,8 @@ LL | if (let 0 = 1) && true {}
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:29:17
|
LL | if true && (let 0 = 1) {}
@ -65,9 +60,8 @@ LL | if true && (let 0 = 1) {}
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:32:9
|
LL | if (let 0 = 1) && (let 0 = 1) {}
@ -75,9 +69,8 @@ LL | if (let 0 = 1) && (let 0 = 1) {}
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:32:24
|
LL | if (let 0 = 1) && (let 0 = 1) {}
@ -85,9 +78,8 @@ LL | if (let 0 = 1) && (let 0 = 1) {}
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:36:8
|
LL | if let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) {}
@ -95,9 +87,8 @@ LL | if let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) {}
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:36:21
|
LL | if let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) {}
@ -105,9 +96,8 @@ LL | if let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) {}
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:36:35
|
LL | if let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) {}
@ -115,9 +105,8 @@ LL | if let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) {}
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:36:48
|
LL | if let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) {}
@ -125,9 +114,8 @@ LL | if let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) {}
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:36:61
|
LL | if let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) {}
@ -135,9 +123,8 @@ LL | if let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) {}
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:43:8
|
LL | if let Range { start: _, end: _ } = (true..true) && false {}
@ -145,9 +132,8 @@ LL | if let Range { start: _, end: _ } = (true..true) && false {}
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:50:12
|
LL | while (let 0 = 1) {}
@ -155,9 +141,8 @@ LL | while (let 0 = 1) {}
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:53:14
|
LL | while (((let 0 = 1))) {}
@ -165,9 +150,8 @@ LL | while (((let 0 = 1))) {}
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:56:19
|
LL | while true && let 0 = 1 {}
@ -175,9 +159,8 @@ LL | while true && let 0 = 1 {}
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:59:11
|
LL | while let 0 = 1 && true {}
@ -185,9 +168,8 @@ LL | while let 0 = 1 && true {}
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:62:12
|
LL | while (let 0 = 1) && true {}
@ -195,9 +177,8 @@ LL | while (let 0 = 1) && true {}
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:65:20
|
LL | while true && (let 0 = 1) {}
@ -205,9 +186,8 @@ LL | while true && (let 0 = 1) {}
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:68:12
|
LL | while (let 0 = 1) && (let 0 = 1) {}
@ -215,9 +195,8 @@ LL | while (let 0 = 1) && (let 0 = 1) {}
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:68:27
|
LL | while (let 0 = 1) && (let 0 = 1) {}
@ -225,9 +204,8 @@ LL | while (let 0 = 1) && (let 0 = 1) {}
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:72:11
|
LL | while let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) {}
@ -235,9 +213,8 @@ LL | while let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) {
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:72:24
|
LL | while let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) {}
@ -245,9 +222,8 @@ LL | while let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) {
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:72:38
|
LL | while let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) {}
@ -255,9 +231,8 @@ LL | while let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) {
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:72:51
|
LL | while let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) {}
@ -265,9 +240,8 @@ LL | while let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) {
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:72:64
|
LL | while let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) {}
@ -275,9 +249,8 @@ LL | while let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) {
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:79:11
|
LL | while let Range { start: _, end: _ } = (true..true) && false {}
@ -285,9 +258,8 @@ LL | while let Range { start: _, end: _ } = (true..true) && false {}
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:99:20
|
LL | #[cfg(FALSE)] (let 0 = 1);
@ -295,9 +267,8 @@ LL | #[cfg(FALSE)] (let 0 = 1);
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:86:17
|
LL | noop_expr!((let 0 = 1));
@ -305,9 +276,8 @@ LL | noop_expr!((let 0 = 1));
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:95:16
|
LL | use_expr!((let 0 = 1 && 0 == 0));
@ -315,9 +285,8 @@ LL | use_expr!((let 0 = 1 && 0 == 0));
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error[E0658]: `let` expressions in this position are experimental
error[E0658]: `let` expressions in this position are unstable
--> $DIR/feature-gate.rs:97:16
|
LL | use_expr!((let 0 = 1));
@ -325,7 +294,6 @@ LL | use_expr!((let 0 = 1));
|
= note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
= help: add `#![feature(let_chains)]` to the crate attributes to enable
= help: you can write `matches!(<expr>, <pattern>)` instead of `let <pattern> = <expr>`
error: aborting due to 33 previous errors

27
src/test/ui/rfc-2497-if-let-chains/irrefutable-lets.rs Normal file
View File

@ -0,0 +1,27 @@
// check-pass
#![feature(let_chains)]
use std::ops::Range;
fn main() {
let opt = Some(None..Some(1));
if let first = &opt && let Some(ref second) = first && let None = second.start {
}
if let Some(ref first) = opt && let second = first && let _third = second {
}
if let Some(ref first) = opt
&& let Range { start: local_start, end: _ } = first
&& let None = local_start {
}
while let first = &opt && let Some(ref second) = first && let None = second.start {
}
while let Some(ref first) = opt && let second = first && let _third = second {
}
while let Some(ref first) = opt
&& let Range { start: local_start, end: _ } = first
&& let None = local_start {
}
}

16
src/test/ui/rfc-2497-if-let-chains/issue-88498.rs Normal file
View File

@ -0,0 +1,16 @@
// check-pass
pub enum UnOp {
Not(Vec<()>),
}
pub fn foo() {
if let Some(x) = None {
match x {
UnOp::Not(_) => {}
}
}
}
fn main() {
}

11
src/test/ui/rfc-2497-if-let-chains/issue-90722.rs Normal file
View File

@ -0,0 +1,11 @@
// check-pass
#![feature(let_chains)]
fn main() {
let x = Some(vec!["test"]);
if let Some(v) = x && v.is_empty() {
println!("x == Some([])");
}
}

11
src/test/ui/rfc-2497-if-let-chains/issue-92145.rs Normal file
View File

@ -0,0 +1,11 @@
// check-pass
#![feature(let_chains)]
fn main() {
let opt = Some("foo bar");
if true && let Some(x) = opt {
println!("{}", x);
}
}

9
src/test/ui/rfc-2497-if-let-chains/no-double-assigments.rs Normal file
View File

@ -0,0 +1,9 @@
// check-pass
fn main() {
loop {
// [1][0] should leave top scope
if true && [1][0] == 1 && true {
}
}
}

35
src/test/ui/rfc-2497-if-let-chains/then-else-blocks.rs Normal file
View File

@ -0,0 +1,35 @@
// run-pass
#![feature(let_chains)]
fn check_if_let(opt: Option<Option<Option<i32>>>, value: i32) -> bool {
if let Some(first) = opt
&& let Some(second) = first
&& let Some(third) = second
&& third == value
{
true
}
else {
false
}
}
fn check_while_let(opt: Option<Option<Option<i32>>>, value: i32) -> bool {
while let Some(first) = opt
&& let Some(second) = first
&& let Some(third) = second
&& third == value
{
return true;
}
false
}
fn main() {
assert_eq!(check_if_let(Some(Some(Some(1))), 1), true);
assert_eq!(check_if_let(Some(Some(Some(1))), 9), false);
assert_eq!(check_while_let(Some(Some(Some(1))), 1), true);
assert_eq!(check_while_let(Some(Some(Some(1))), 9), false);
}