> >Are you sure using lists instead of vectors is the right thing to do? > > Lists are linked lists and as such accessing the i'th element is O(i). In > > vectors it is O(1). This can cause an order of complexity increase in > > handling them. This is true, but not much of a problem, since most scripts only use either the first 1 or 2 elements of arrays or work on typically very short arrays, or want to pass a (short) array to PDB, where there is no difference between list-construction and setting every element of a vector explicitly (the latter possibly being even more inefficient). > No, I'm not sure. For the few scripts I looked at (and for ease of > implementation), using a list was the easier route to have something > functional during the early development stages. Using vectors instead of a > simple list would mean the ability to use functions which would provide > rough equivalents to the SIOD interpreters array manipulation functions. As I understand it, there are even *exact* equivalents to the current "array" type. No wonder, since a Lisp vector is a special case of an array (one-dimensional). In Script-Fu, "arrays" are indeed vectors. > I will take a closer look at using vectors. It will simplify the work > needed to update old Script-Fu scripts for use with Tiny-Fu. I will start > by converting between list and vector. If the approach works well, I will > bit the bullet and update the marshalling code to use vectors for the > *ARRAY types. I also opt for vector because apart from being the natural Scheme equivalent to PDB's one-dimensional arrays, it makes writing plug-ins easier for people that have no to little practice in converting common "for/while" loops using tail-recursion, and current scripts would work practically unmodified, without explicit conversions list->vector that would only cost time (with everybody ending up calling these instead of working on lists most of the time). Markus.
