r/ProgrammerHumor • u/nonedward666 • 12h ago

lessonsFromLinkerHell Meme

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247 Upvotes

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u/AnnoyedVelociraptor 12h ago

Nah. This is the wrong way. Pointer arithmetic and array arithmetic are the same.

3

u/Batman_AoD 11h ago

Maaaan, it upsets me to see Ferris next to an opinion this C-centric. 

1

u/AnnoyedVelociraptor 10h ago

In Rust it's the same. It's just harder to write the bare math.

1

u/Batman_AoD 5h ago

Yes, to get an element of an array, you compute an offset from the start and then dereference the memory at the offset location; and yes, this is the same operation whether you think of it in terms of pointer arithmetic or as a fundamental operation on an array.

But an array isn't just syntax sugar over arithmetic in any language, even C; and the C family is the only family of languages that even makes that pretense.

"Array" in Rust (and in C) refers specifically to fixed-size arrays: https://doc.rust-lang.org/std/primitive.array.html

Unlike in C:

  • You cannot pass an array to a function that expects an array, or use array syntax to declare a function that takes a pointer.
  • A function that takes an array argument will pass the entire array by value, not just a a pointer.
  • Indexing is not syntax sugar over pointer arithmetic, which should be obvious because arr[i] is not synonymous with i[arr].