With (fifteenth RacketCon) coming up, we will once again be running out of list accessors in racket/list soon. Fortunately, with the new c(a|d)ⁿr release now providing list accessors into the millions and beyond, this pressing issue can finally be solved for good:
> (require cadnr)
> (define RacketCon
(for/list ([year (in-range twenty-eleven one-million)])
`(RacketCon ,year)))
; --------------- before ... ---------------
> (cadddddddddddddddddddddddddddr RacketCon) ;; hmm yes, this is lovely, but...
'(RacketCon 2038); ^ 18... 19... ah! I lost count :(
; --------------- after... ---------------
> (twenty-eighth RacketCon) ;; perfect!
'(RacketCon 2038)
It doesn't stop there, though! The new c(a|d)ⁿr knows about all sorts of numbers and containers, even those that haven't been written yet:
> (vector-fifth (list 1 2 3 4 5))
5
> (string-last "abcdefghijklmnopqrstuvwxyz")
; this one's clearly not that useful, writing out
; (string-ref s (sub1 (string-length s)))
; is far easier on the eyes
#\z
> (non-empty-vector? (vector 1))
; analogous to the venerable non-empty-string?
#t
> (string-empty? "")
#t
> (require math/flonum)
> (define flvec (build-flvector ten-million (compose fl add2011)))
; unlike sequence-ref, cadnr accessors always
; use type-ref for maximum performance
> (time (sequence-two-millionth flvec)) ; linear time :(
cpu time: 45 real time: 46 gc time: 5
2002010.0
> (time (flvector-two-millionth flvec)) ; constant time! :)
cpu time: 0 real time: 0 gc time: 0
2002010.0
Read the documentation, and try it out today!
