... { () => 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 }
 | + +
```

```
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;
 | + +
```