Lower the precedence of the as operator.
#1951
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Previously, the `as` operator was being parsed like a postfix expression, and therefore being given the highest possible precedence. That caused it to bind more tightly than prefix operators, which it should not. Instead, parse it somewhat like a normal binary expression with some special-casing.
matklad
reviewed
Oct 4, 2019
| @@ -296,6 +301,7 @@ fn lhs(p: &mut Parser, r: Restrictions) -> Option<(CompletedMarker, BlockLike)> | |||
| // fn foo() { | |||
| // let _ = &1; | |||
| // let _ = &mut &f(); | |||
| // let _ = &1 as *const i32; | |||
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Let's move this test to the if p.at(T![as]) { line
| // *&1 as u64; | ||
| // *x(1); | ||
| // &x[1]; | ||
| // -1..2; |
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Let's move these additional cases to an out-of-line test somewhere in test-data/parser/ok. The purpose of the inline tests is not to exhaustively check everything, but to explain what the code immediately after them does, and, for that purposes, simple cases are more useful.
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Done :) |
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bors r+ Thanks! |
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Oct 8, 2019
1951: Lower the precedence of the `as` operator. r=matklad a=goffrie Previously, the `as` operator was being parsed like a postfix expression, and therefore being given the highest possible precedence. That caused it to bind more tightly than prefix operators, which it should not. Instead, parse it somewhat like a normal binary expression with some special-casing. Fixes #1851. Co-authored-by: Geoffry Song <goffrie@gmail.com>
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Previously, the
asoperator was being parsed like a postfix expression, andtherefore being given the highest possible precedence. That caused it to bind
more tightly than prefix operators, which it should not. Instead, parse it
somewhat like a normal binary expression with some special-casing.
Fixes #1851.