- guf_stack, guf_queue, guf_dqueue, guf_prio_queue (using a heap), guf_ringbuf
- sort: add cpp #ifdef to remove restrict from declaration

- guf_wrapping_mul_TYPE: Not 100 % sure if it does not depend on implementation defined behaviour, but it shouldn't
- https://en.cppreference.com/w/c/types/integer (apparently the signed fixed width integer types are guaranteed to be two's complement...)

- tests for guf_dict with GUF_DICT_64_BIT_IDX (and also hash32/hash64); maybe pass kv_type to insert to avoid copy
- dict elems shrink to fit; allow to pass GUF_DBUF_USE_GROWTH_FAC_ONE_POINT_FIVE; start capacity (for elems and kv_indices?)
- dict: if load factor is high due to mostly tombstones, just try rehashing without resizing first?

- bench

- no guf_init.h

- unicode normalisation
- handle right-to-left text properly