In python, when i'm making a slice of array/string/etc, python create a new object in memory, so what exactly happens when I'm making the same in Rust?
let s = String::from("hello");
let slice = &s[..];
println!("{slice_copy}")
here, slice is just reference to whole object in memory(like &s), or rust create a new string object in memory?
It's a wide reference (pointer and length).
It doesn't duplicate the data.
The signature of the Index::index trait method (that implements the bracket indexing syntax) is
fn index(&self, index: I) -> &Self::Output;
which implies that indexing can't (sensibly) be implemented by creating a new object.
(You could heap-allocate and leak it or borrow a static, but you can't return a reference to a properly memory-managed local. Thus, the returned reference can only come from within self.)
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