alt Hacker News> C Strings at least let you take a zero copy substring of the tail
This is a special-case optimisation that I'm happy to lose in favour of the massive performance and security benefits otherwise.
Isn't length + pointer... Basically a Pascal string? Unless I am mistaken.
I think what was unsaid in your second point is that we really need to type-differentiate constant strings, dynamic strings, and string 'views', which Rust does in-language, and C++ does with the standard library. I prefer Rust's approach.
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> Isn't length + pointer... Basically a Pascal string? Unless I am mistaken.
Length + pointer is a record string, a pascal string has the length at the head of the buffer, behind the pointer.
Pascal strings store the string's length by its data, whereas fat pointers store the length by the address of the data.
The main difference is that if a string's length is by its data, you can't easily construct a pointer to part of that data without copying it into a new string, whereas if instead the length is by the data's address, you can cheaply construct pointers to any substring (by coming up with new length+address pairs) without having to construct entire new strings.
If I recall correctly a pascal string has the length before the string. Ie to get the length you dereference the pointer and look backwards N bytes to get the length. A pascal string is still a single pointer.
You cannot cheaply take an arbitrary view of the interior string - you can only truncate cheaply (and oob checks are easier to automate). That’s why pointer + length is important because it’s a generic view. For arrays it’s more complicated because you can have a stride which is important for multidimensional arrays.