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A comment on My first verified imperative program. Parent comment

Re:My first verified imperative program by sureglymop on Tuesday July 08, 2025 @12:40AM (#44497130)
How so? If you specify the type int how would that save you from an overflow/underflow at runtime?
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Re:My first verified imperative program by alternatex on Tuesday July 08, 2025 @10:42AM (#44500452)
Not sure if types are supposed to protect against overflow/underflow, it's more in the arithmetic territory. Interesting idea though, I wonder if some programming language allows overflow/underflow checks directly in the types.
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Re:My first verified imperative program by Joker_vD on Friday July 11, 2025 @06:42AM (#44530618)
Yes, it's actually quite easy:

    +: (int<N>, int<N>) -> int<N+1>    // or (int<N>, bit) as the return type
    *: (int<N>, int<N>) -> int<2*N>
etc. Those are the actual types of those arithmetic operations.
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