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marcosdumay • yesterday at 6:24 PM • 2 replies • view on HN

Applying the increment or decrement operators over the same variable more than once on the same line should be a compile-time error.

Anyway, yes, this one example has an obvious order it should be applied. But still, something like it shouldn't be allowed.

Replies

nayuki • yesterday at 7:15 PM

> Applying the increment or decrement operators over the same variable more than once on the same line should be a compile-time error

That would be nice, but don't forget the more general case of pointers and aliasing:

    int a = 5;
    int *pa = &a;
    printf("%d", (a++ + ++*pa));
The compiler cannot statically catch every possible instance of a statement where a variable is updated more than once.
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saghm • yesterday at 6:37 PM

Honestly, having increment in expressions rather than a statement feels like more of a footgun than a benefit. Expressions shouldn't mutate things.

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