Suggest parentheses when match or if expression in binop is parsed as statement
#146044
Conversation
… { () => 1 }`
```
error[E0308]: mismatched types
--> $DIR/expr-as-stmt.rs:69:5
|
LL | match () { () => 1 } + match () { () => 1 }
| ^^^^^^^^^^^^^^^^^^^^ expected `()`, found integer
|
help: consider using a semicolon here
|
LL | match () { () => 1 }; + match () { () => 1 }
| +
help: alternatively, parentheses are required to parse this as an expression
|
LL | (match () { () => 1 }) + match () { () => 1 }
| + +
```
Parentheses are needed for the `match` to be unambiguously parsed as an expression and not a statement when chaining with binops that are also unops.
…expression
```
error[E0308]: mismatched types
--> $DIR/expr-as-stmt.rs:69:5
|
LL | match () { () => 1 } + match () { () => 1 }
| ^^^^^^^^^^^^^^^^^^^^ expected `()`, found integer
|
help: parentheses are required to parse this as an expression
|
LL | (match () { () => 1 }) + match () { () => 1 }
| + +
```
|
r? @SparrowLii rustbot has assigned @SparrowLii. Use |
rustbot
added
S-waiting-on-review
|
r? @chenyukang |
```
error[E0308]: mismatched types
--> $DIR/expr-as-stmt-2.rs:15:15
|
LL | if true { true } else { false } && true;
| ----------^^^^-----------------
| | |
| | expected `()`, found `bool`
| expected this to be `()`
|
help: parentheses are required to parse this as an expression
|
LL | (if true { true } else { false }) && true;
| + +
```
estebank
changed the title
match expression in binop is parsed as statementmatch or if expression in binop is parsed as statement
| @@ -1897,7 +1897,7 @@ impl<'tcx, 'exprs, E: AsCoercionSite> CoerceMany<'tcx, 'exprs, E> { | |||
| fcx.suggest_semicolon_at_end(cond_expr.span, &mut err); | |||
| } | |||
| } | |||
| }; | |||
| } | |||
There was a problem hiding this comment.
do we have a style lint to check this?
|
@bors r=chenyukang |
bors
added
S-waiting-on-bors
|
☀️ Test successful - checks-actions |
What is this?This is an experimental post-merge analysis report that shows differences in test outcomes between the merged PR and its parent PR.Comparing c559c4a (parent) -> 9cd272d (this PR) Test differencesShow 30 test diffs30 doctest diffs were found. These are ignored, as they are noisy. Test dashboardRun cargo run --manifest-path src/ci/citool/Cargo.toml -- \
test-dashboard 9cd272dc85320e85a8c83a1a338870de52c005f3 --output-dir test-dashboardAnd then open Job duration changes
How to interpret the job duration changes?Job durations can vary a lot, based on the actual runner instance |
|
Finished benchmarking commit (9cd272d): comparison URL. Overall result: no relevant changes - no action needed@rustbot label: -perf-regression Instruction countThis benchmark run did not return any relevant results for this metric. Max RSS (memory usage)Results (primary 0.6%, secondary 0.9%)A less reliable metric. May be of interest, but not used to determine the overall result above.
CyclesResults (primary -1.8%)A less reliable metric. May be of interest, but not used to determine the overall result above.
Binary sizeThis benchmark run did not return any relevant results for this metric. Bootstrap: 469.348s -> 466.363s (-0.64%) |
Address the common case from #88727. The original parse error is still outstanding, but the cases brought up in the thread are resolved.