Re: [Bug-apl] performance in of ¨

[Juergen Sauermann]

Hi, I believe I have fixed the problem, SVN 749. The fault was actually not related to macros but a general problem affecting the performance of virtually all workspaces. The time-consuming line in the EACH macro was this: LOOP: Z[N]←⊂(⊃A[N]) LO ⊃B[N] ◊ →(N_max>N←N+1)⍴LOOP Due to an inefficiency in the runtime parser, the parser would, for example, first resolve B (which creates a copy of B) and then index the copy to obtain B[N] . Same for A. If B has N items then this would generate N copies of B, each copy taking O(N) cycles, and therefore the runtime of the above innocent looking LOOP would be O(N×N). Macros are a little slower than their built-in siblings, but the code that could be removed by using macros belonged to the most error-prone in the past, and some of the built-in operators (which are called when their function argument(s) are primitive functions) could also be simplified. /// Jürgen