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parens are not optional in guard chains that have || operators #2224

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parens are not optional in guard chains that have || operators #2224

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0ed6d4f
parens are not optional in guard chains that have || operators
tshepang Apr 11, 2026
e81dd7c
another occurance
tshepang Apr 11, 2026
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2 changes: 1 addition & 1 deletion src/expressions/if-expr.md
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Expand Up @@ -186,7 +186,7 @@ fn nested() {
```

r[expr.if.chains.or]
If any condition operand is a `let` pattern, then none of the condition operands can be a `||` [lazy boolean operator expression][expr.bool-logic] due to ambiguity and precedence with the `let` scrutinee. If a `||` expression is needed, then parentheses can be used. For example:
If any condition operand is a `let` pattern, then none of the condition operands can be a `||` [lazy boolean operator expression][expr.bool-logic] due to ambiguity and precedence with the `let` scrutinee. If a `||` expression is needed, then parentheses must be used. For example:
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@ehuss ehuss Apr 28, 2026 •
edited by rustbot
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I don't think it is correct to use "must" here. This is saying that this is an option for how to work around the limitation. For example, you could sometimes use curly braces, or lift parts out to a variable, or don't use chains.

I think the correct change would be to move this statement out to an example block like the other one, since it isn't a language rule.

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```rust
# let foo = Some(123);
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2 changes: 1 addition & 1 deletion src/expressions/match-expr.md
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Expand Up @@ -235,7 +235,7 @@ r[expr.match.guard.chains.or]
If any guard condition operand is a `let` pattern, then none of the condition operands can be a `||` [lazy boolean operator expression][expr.bool-logic] due to ambiguity and precedence with the `let` scrutinee.

> [!EXAMPLE]
> If a `||` expression is needed, then parentheses can be used. For example:
> If a `||` expression is needed, then parentheses must be used. For example:
>
> ```rust
> # let foo = Some([123]);
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