75         // SAFETY: This is one of the invariant of `CStr`.  in len_with_nul()
92     /// # Safety
99         // SAFETY: The safety precondition guarantees `ptr` is a valid pointer  in from_char_ptr()
102         // SAFETY: Lifetime guaranteed by the safety precondition.  in from_char_ptr()
104         // SAFETY: As `len` is returned by `strlen`, `bytes` does not contain interior `NUL`.  in from_char_ptr()
129         // SAFETY: We just checked that all properties hold.  in from_bytes_with_nul()
136     /// # Safety
142         // SAFETY: Properties of `bytes` guaranteed by the safety precondition.  in from_bytes_with_nul_unchecked()
185     /// # Safety
194     /// // SAFETY: String literals are guaranteed to be valid UTF-8
295         // SAFETY: We just checked the bounds.  in index()
415     /// # Safety
420         // INVARIANT: The safety requirements guarantee the type invariants.  in from_ptrs()
430     /// # Safety
436         // INVARIANT: We ensure that `end` is never less then `buf`, and the safety requirements  in from_buffer()
468             // SAFETY: If `len_to_copy` is non-zero, then we know `pos` has not gone past `end`  in write_str()
492     /// # Safety
497         // SAFETY: The safety requirements of this function satisfy those of the callee.  in from_buffer()
562         // SAFETY: The buffer stored in `buf` is at least of size `size` and is valid for writes.  in try_from_fmt()
567         // SAFETY: The number of bytes that can be written to `f` is bounded by `size`, which is  in try_from_fmt()
572         // SAFETY: The buffer is valid for read because `f.bytes_written()` is bounded by `size`  in try_from_fmt()
590         // SAFETY: The type invariants guarantee that the string is `NUL`-terminated and that no  in deref()