Do not desugar if-let-else to match arm guards #41316
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r? @eddyb |
src/librustc/hir/lowering.rs
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| let wildcard_arm: Option<&Expr> = else_opt.as_ref().map(|p| &**p); | ||
| let wildcard_pattern = self.pat_wild(e.span); | ||
| let body = if let Some(else_expr) = wildcard_arm { | ||
| P(self.lower_expr(else_expr)) |
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This and the else branche below it should be indented one time (4 spaces) to the left.
src/test/run-pass/issue-41272.rs
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| fn bar(&mut self) -> bool { true } | ||
| } | ||
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| /* This causes E0301. By fixing issue #41272 this problem should vanish */ |
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We don't use block comments, nor is this comment necessary here. FWIW error codes are also kind of useless since they say nothing about the actual error.
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@bors r+ |
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📌 Commit 5649b37 has been approved by |
Do not desugar if-let-else to match arm guards Fixes #41272 Changed the desugaring code **Before** ```rust match <sub_expr> { <pat> => <body>, [_ if <else_opt_if_cond> => <else_opt_if_body>,] _ => [<else_opt> | ()] } ``` **After** ```rust match <sub_expr> { <pat> => <body>, _ => [<else_opt> | ()] } ``` With this fix, it doesn't cause E0301
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☀️ Test successful - status-appveyor, status-travis |
Fixes #41272
Changed the desugaring code
Before
After
With this fix, it doesn't cause E0301