- Ropes enable much faster insertion and deletion of text in comparison to string arrays, on which the operations have a time complexity of
O(n). For example strings concatenation function is able to work in constant time because, at most, it has to allocate a single concatenation node.
- Ropes do not require
O(n) extra memory when being operated upon, unlike arrays which require it for copying operations.
- Ropes do not need large contiguous memory areas like arrays.
- If the operations performed are non-destructive (i.e the altered content is preserved) it behaves as a persistent data structure. This helps the text editors support multiple undo levels.
- Certain operations may reuse the previous rope sections to allow sharing in memory. Minor modifications of a rope can share memory with the original. Ropes are allocated in small chunks, significantly reducing memory fragmentation problems introduced by large blocks.
- Ropes allow deferred loading of substrings until required.
- Assignment is simply a (possibly reference counted) pointer assignment. Unlike reference-counted copy-on-write implementations, this remains largely true even if one of the copies is subsequently slightly modified. It is very inexpensive to checkpoint old versions of a string, e.g. in an edit history.
- Stable performance regardless of size.
VietMX Staff asked 3 years ago
