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//@ run-pass
#![allow(unused_must_use)]
#![allow(unused_parens)]
// This test has some extra semis in it that the pretty-printer won't
// reproduce so we don't want to automatically reformat it
// no-reformat
/*
*
* When you write a block-expression thing followed by
* a lone unary operator, you can get a surprising parse:
*
* if (...) { ... }
* -num;
*
* for example, or:
*
* if (...) { ... }
* *box;
*
* These will parse as subtraction and multiplication binops.
* To get them to parse "the way you want" you need to brace
* the leading unops:
* if (...) { ... }
* {-num};
*
* or alternatively, semi-separate them:
*
* if (...) { ... };
* -num;
*
* This seems a little wonky, but the alternative is to lower
* precedence of such block-like exprs to the point where
* you have to parenthesize them to get them to occur in the
* RHS of a binop. For example, you'd have to write:
*
* 12 + (if (foo) { 13 } else { 14 });
*
* rather than:
*
* 12 + if (foo) { 13 } else { 14 };
*
* Since we want to maintain the ability to write the latter,
* we leave the parens-burden on the trailing unop case.
*
*/
pub fn main() {
let num = 12;
assert_eq!(if (true) { 12 } else { 12 } - num, 0);
assert_eq!(12 - if (true) { 12 } else { 12 }, 0);
if (true) { 12; } {-num};
if (true) { 12; }; {-num};
if (true) { 12; };;; -num;
//~^ WARNING unnecessary trailing semicolons
}
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